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2011 Montreal Montreal
2012
Montreal
2012
Processing – Ferrous Metallurgy
Ferrous Processing 1
The Use of FactSage
in
Steelmaking Processes
In-Ho Jung
Dept. of Mining and Materials Eng., McGill Univ.
[email protected] Tel: 1-514-398-2608
2011 Montreal Montreal
2012
Montreal
2012
Contents
Ferrous Processing 2
• Databases in FactSage for steelmaking applications
• Most common phase diagrams for steelmaking applications
• Simple examples of Equilib for various functions of FactSage:
Trget/Transition, Stream, Heat balance, Open, Fixing partial pressure,
Fe saturation, etc.
• Simple examples of Phase diagram for various functions of FactSage:
Binary diagram, Ternary and multi-component - Isothermal, isopleth diagram.
• Application: Activity calculations in binary, ternary and multi-component systems
Slag and FeLq
• Application: Addition of new component (user defined) to Slag: V2O3 oxide in slag
Henrian activity coefficient
• Application: Addition of new compound and solution (user defined) in calculations:
MnCr2O4-MnAl2O4 ideal solid solution
• Application: Phase diagram calculations (advanced)
Phase diagram calculations with Fe oxide and Fe saturation:
Multi-component phase diagrams, slag – refractories or inclusions
• Application: Non-metallic Inclusions (inclusion formation, stability diagram)
• Application: Solidification (Scheil cooling) of slag and steel
• Application: Refractory design (thermodynamic stability)
• Macro processing: Process simulations (simple/advanced examples, Rotary Kiln, etc)
• Viscosity module: Slag and Glass viscosity calculations
• FactOptimal module: Process condition optimization / new alloy development
2011 Montreal Montreal
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2012 Ferrous Processing 3
Databases in FactSage for steelmaking
applications
Brief History of Database Development
Details of Oxide Solution Database for Steelmaking Applications
2011 Montreal Montreal
2012
Montreal
2012
Database in FactSage
Brief History of FACTSAGE Database Development
1976~2001: F*A*C*T 2001~present: FactSage (a fusion of F*A*C*T + ChemSage)
< 1998 : FACT database (before 1998)
1999~2003 : FACT53 database
2000~2004 : FACT Consortium project (2000~2004): 16 companies
pyrometallurgy (ferrous, non-ferrous), hydrometallurgy-corrosion, glassmaking
- FACT53 database FToxid, FTmisc, FThall, FTsalt, FThelg,..
- New alloy databases: FSStel, FSlite, FScopp, SGTE, ….
2004~2010 : Mini-consortiums
- Al consortium (Alcoa, Alcan, and Norsk-Hydro)
- Glass consortium (Corning, Schott, and Saint-Gobain)
- Light alloy (Al, Mg) consortium (Al consor., GM and MagNET): FTlite
- Steelmaking consortium (Posco, RIST, and Tata Steel Europe)
2011~2014 : Mini-consortiums
- Al consortium (3 companies), Glass consortium (3 companies)
- Steelmaking consortium: 11 companies Consortium database (‘CON1’)
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2011 Montreal Montreal
2012
Database in FactSage for Steelmaking Applications
FACTPS: All gaseous species, stoichiometric solid and liquid species
(organic, inorganic)
Similar to thermodynamic table like JANAF, Barin-Kubaschewski
FToxid: Most updated Oxide database with
- many solution phases (slag, spinel, monoxide, olivine, etc.)
- pure solid and liquid oxides, No gas phase
FTmisc: FeLq solution
- most reliable liquid steel database for steelmaking calculations
(slags/refractories/gases/molten iron)
FSStel: solid and liquid steel phases
(also includes small number of gases, oxides, sulfides, nitrides, etc.)
- for steel solidifications and alloy design.
- liquid steel: reasonable calculations for steelmaking applications
For steelmaking calculations:
priority: FToxid > FeLq > FACTPS
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2012
FToxid database
Main solution phases when T > 1550oC (steelmaking)
Slag (I option): CaO-MgO-Al2O3-SiO2-FeO-Fe2O3-MnO-Mn2O3-Ti2O3-TiO2…
+ Gas solubility such as S (SO2), P, H (OH), N, C, F, …
Spinel (I option) (SPIN): (Mg,Fe,Mn,Co,Ni,Zn)(Al,Fe,Cr,Co,Mn,Va)2O4, extensive solid solution
containing MgAl2O4, MgCr2O4, MgFe2O4, FeCr2O4, Fe3O4, FeAl2O4, Cr3O4, MnAl2O4,
MnCr2O4, MnFe2O4, etc.
(AlSp): (Fe,Mg,Mn)Al2O4-Al2O3 solution
a-, a’-Ca2SiO4 (aC2S, bC2S): Ca2SiO4 (C2S) rich solution with limited solubility of Mg2SiO4,
Fe2SiO4, Mn2SiO4,etc.
Olivine (Oliv): Mg2SiO4, Fe2SiO4, etc. (Mg,Fe,Ca,Mn,Ni,Zn,Co,Cr,etc.)2SiO4, covering
forsterite (Mg2SiO4), fayalite (Fe2SiO4), -Ca2SiO4, monticellite CaMgSiO4, tephroite Mn2SiO4.
I option specially when Ca2SiO4 exists.
Corundum (CORU): (Al,Cr,Fe,Mn)2O3 solution, the solution of Al2O3, Cr2O3 and Fe2O3. Solid
miscibility gaps exist between the constituents. I option required.
Monoxide (halite) (MeO_): of CaO-MgO-FeO-MnO-NiO-Fe2O3-Al2O3-Cr2O3 etc. well-known
lime (CaO), periclase (MgO) and wustite (FeO). I option especially when CaO and MgO exist
together.
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2012
Mn/Ti oxides:
i) ilmenite (ILME): (FeTiO3(ilmenite)–Ti2O3–MgTiO3–MnTiO3 + Al2O3),
ii) pseudo-brookite (PSEU): (Ti3O5–FeTi2O5-MgTi2O5–MnTi2O5 ),
iii) Ti-spinel (TiSp): (Mg,Fe,Mn)[Mg,Fe,Mn,Ti,Al]2O4
iv) Rutile (TiO2):TiO2 + Ti2O3-ZrO2 solid solution
Mullite (Mull): non-stoichiometric Al6Si2O13 with possible solubility of B.
(MulF): stoichiometric Al6Si2O13 with dilute Fe6Si2O13.
Melilite (Mel_): Ca2[Mg,Fe2+,Fe3+,Al](Fe3+,Al,Si)2O7. Akermanite Ca2MgSi2O7 and gehlenite
Ca2Al2SiO7 form the melilite solid solution stable below 1590 °C.
Main solution phases when T < 1550oC (solidification of slag)
Wollastonite (Woll): (Ca,Mg,Mn)SiO3, which is a CaSiO3 rich phase stable below 1300 °C.
Pseudo-wollastonite is stoichiometric CaSiO3 stable below 1550 °C.
pyroxene (pPyr, oPyr, cPyr): (Mg,Ca,Fe)[Mg,Fe]Si2O6, which is a MgSiO3-rich phase stable
below 1560 °C. proto-, ortho-, low-clino-pyroxene exist. Clino-pyroxene is a CaMg2SiO6-rich
phase, which is stable below 1390 °C.
Rhodonite (Rhod): (Mn,Ca)SiO3, a MnSiO3-rich solid stable below 1300 °C.
FToxid database
Ferrous Processing 7
2011 Montreal Montreal
2012
Main solution phases in CaO-Al2O3-SiO2-FetO system when high PO2 (air)
CAFS Ca2(Al,Fe)8SiO16, CAF6 Ca(Al, Fe)12O19, CAF3 Ca(Al,Fe)6O10, CAF2 Ca(Al,Fe)4O7
CAF1 Ca(Al,Fe)2O4, C2AF Ca2(Al,Fe)2O5, C3AF Ca3(Al,Fe)2O6
Main solution phases when T < 1550oC (mould flux, Na2O containing system)
Nepheline (Neph): NaAlSiO4 with excess SiO2.
Carnegeite (Carn): NaAlSiO4 with excess SiO2.
NaAlO2 (NASl): low temperature - NaAlO2 with excess NaAlSiO4
NaAlO2 (NASh): high temperature - NaAlO2 with excess NaAlSiO4
Combeite (NCSO): Na4CaSi3O9 (bombeite) – Na2Ca2Si3O9 solid solution
Feldspar (Feld): complete solution between Anorthite(CaAl2Si2O8)-Albite(NaAlSi3O8)
NCA2: (Na2,Ca)O·Na2O·2Al2O3 solid solution
C3A1: Ca3Al2O6 dissolving Na2O, (Ca,Na2)1Ca8Al6O18 solution
Most updated version of Na2O containing system in available in “CON1” database
FToxid database
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FTmisc (FeLq) and FSStel
FeLq Liquid Fe containing Ag,Al,B,Ba,C,Ca,Ce,Co,Cr,Cu,H,Hf,La,Mg,Mn,Mo,N,Nb,Nd,Ni,O,P,Pb,Pd,S,Si,
Sn,Ta,Th,Ti,U,V,W,Zr. This phase is better suited for calculations involving iron and steelmaking
processes (optimized for iron-rich solutions only).
Based on the Unified Interaction Parameter Formalism (advanced than Classical Wagner’s
Interaction parameter formalism) with associate model for deoxidation. Many interaction
parameters between metallic elements are taken from JSPS (Japanese compilation)
FSStel database FCC/BCC: Fe / Carbide / Nitride are all treated as FCC phases
Fe with N and C : use J option (3-miscibility gaps).
Fe with N or C : use I option (2-miscibility gaps).
Also recommend to use I option for BCC phase For example, see Fe-Ti-Nb-C-N example.
Liquid: O and S are treated as associate model
FCC ordered phase (FCC_L12), BCC ordered phase (BCC_B2) normally slow down the
calculations significantly. If you are not really interested in order/disorder transitions, do not to select
these phases.
Carbon: when C content is lower than ~ 1%, Fe3C (metastable) phase is normally formed instead
of C (stable). So, in the selection of solid phases, “unselect” C solid phases.
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2012 Ferrous Processing 10
Most common phase diagrams for
Steelmaking Applications
CaO-MgO-SiO2-Al2O3-FetO-MnO
Na2O-CaO-Al2O3-SiO2
MnO-TiO2
2011 Montreal Montreal
2012
Phase vs. Phase diagram
Fe(liquid)+MW+Slag
Schenck and Pfaff[54]
Gokcen[69]
Fischer and Ende[72]
Taylor and Chipman[70]
Shim and Ban-Ya[74]
Fe(liquid)+MW
Fe(bcc) + MW
Fe(fcc) + MW
Fe(liquid)+Slag
Scheel et al.[73]
Fetters and Chipman[71]
molar ratio FeO/(MgO+FeO)
Tem
per
atu
re,
oC
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
1000
1200
1400
1600
1800
2000
2200
2400
2600
2800
3000
Slag
Lime
Wustite
Ca2Fe2O5 + WustiteLime + Ca2Fe2O5
Lime+Wustite
Lime + Slag
Zhao et al.[45]
Abbatista[20]
Allen and Snow[17]
Larson[21]
Takeda[22]
Timucin[23]
Ca
2F
e2O
5
1059oC
1125oC
1371oC
0.760.16
0.13
0.67
0.72
mass FeO/(CaO+FeO)
Tem
peratu
re, oC
0 0.2 0.4 0.6 0.8 1
800
1000
1200
1400
1600
1800
Monoxide; halite solution (MeO_)
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Phase vs. Phase diagram
MnO
Liquid
2 Liquids
SiO2(Crist)
SiO2(Trid)
MnSiO3Mn2SiO4
1842oC
1328oC
1251oC
1347oC
1293oC
1465oC
1702oC
0.59 0.992
0.490.43
0.29
mole fraction MnO
Tem
pera
ture
(oC
)
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
1200
1300
1400
1500
1600
1700
1800
1900
Olivine: M2SiO4
MgSiO3-rich: pyroxene
MnSiO3-rich: rhodonite
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2011 Montreal Montreal
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Liquid
Mullite(Al6Si2O13)
Al2O3
SiO2(Trid)
SiO2(Crist)
1890oC 1890
oC
1465oC
1596oC 0.96
0.334
2054oC
1723oC
mole fraction SiO2
Tem
pera
ture
(oC
)
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
1200
1300
1400
1500
1600
1700
1800
1900
2000
2100
2504oC
1769oC
1527oC 0.77
0.55
1842oC
MnO
Mn
Al 2
O4
Al2O3
Jacob[16]
Olsen & Heynert[17]
mole fraction MnO
Tem
pera
ture
(oC
)
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
1000
1100
1200
1300
1400
1500
1600
1700
1800
1900
2000
2100
2200
Al 2
O3
Spinel
Alper et al[22]
Viechnicki et al[23]
Saalfeld and Jagodzinski[32]
Viertel and Seifert[30]
Mori[24]
Stubican and Roy[25]
Henriksen and Kingery[27]
Whitney and Stubican[28]
Rankin and Merwin[21]
2122
(1994, 0.79)
2054
2825
0.07
Frenkel et al[26]
Roy et al[31]
Shirasuka and Yamaguchi[29]
Lejus[33]
(1985, 0.36)
(2008, 0.92)
Liquid
Mo
no
xid
e 0.90
MgO mole fraction Al2O3
Tem
pera
ture,
oC
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
1000
1200
1400
1600
1800
2000
2200
2400
2600
2800
3000
Slag
MW+Slag
SpinelMW
Slag
Spinel
Spinel + Fe2O3
MW + Spinel
MW + Slag
Roberts and Merwin[66]: phase boundaries
Willshee and White[65]: invariant points
Slag+Solid
Woodhouse and White[39]: monoxide boundary
MW+Spinel
MW
1711
Schurmann and Kolm[68]: Slag
Phillips et al.[67]
molar ratio Fe2O3/(MgO+Fe2O3)
Tem
per
atu
re,
oC
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
800
1000
1200
1400
1600
1800
2000
2200
2400
2600
2800
3000Spinel: A2+(B3+)2O4
Mullite
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Phase vs. Phase diagram
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2012
Phase vs. Phase diagram
AOlivine
Fe(liq)
Fe(s)
Fe(s2)
ASlag-liq + AOlivine
Fe(s)
ASlag-liq
Mg2SiO4 - Fe2SiO4 - Fe
Fe/(Mg2SiO
4+Fe
2SiO
4) (mol/mol) = 0.001
Fe2SiO4/(Mg2SiO4+Fe2SiO4) (mol/mol)
T(C
)
0 0.2 0.4 0.6 0.8 1
1000
1100
1200
1300
1400
1500
1600
1700
1800
1900
2000
Fe saturation
Ferrous Processing 15
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2012
Phase vs. Phase diagram
Ferrous Processing 16
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2012
Phase vs. Phase diagram
1422
2374
1542
1349
1985
1333
1309
1597
15221344
1362
1714
1754
16902008
1778
1758
1708
1833CaO
MgO
Al2O3(2572) (2054)
(2825)
Mole fraction
2600
2400
2200
2000
1800
1600
2100
1900
1700
15001400
MgO
Spinel
CaO
Al2O3
CaAl12O19Ca3Al2O6
CaAl2O4
(1604)
CaAl4O7
(1765)
Ca3MgAl4O8
CaMg2Al16O27
Ca2Mg2Al28O46
1766
2122
MgO Al2O3
SiO2SiO2SiO2SiO2SiO2SiO2SiO2SiO2SiO2SiO2SiO2SiO2SiO2
1435
1465
1454
1575
weight percent
1381
1445
1361
1371
1558
1548
16451863
Tw
o-L
iquid
s
SiO2(Crist)
SiO2(Trid)
Cordierite
Sapphirine
2000
1900
1800
2600
2400
2200
2000
1700
1600
1500
1400
2000
1600
1500
MgOSpinel
Al2O3
Mullite
Mg2SiO4
MgSiO3
20081985
(Mg2Al4Si5O18)
(Mg4Al10Si2O23)
(1723)
(2825) (2054)
12391328
1769
Corundum
Galaxite
Mullite
Mn2SiO4
MnSiO3
MnO
SiO2
1293
Al6Si2O13
(1890)(1347)
MnAl2O4
(2054)(1842)
(1723)
1595
1702
1890
1465
Mn2Al4Si5O18
(Mn-Cordierite)
2000
1900
1800
1700
1600
(1180)
MnO
Al2O3
1135
1119
1156
1800
1700
1600
Mn3Al2Si3O12
(Spessartite)(1200)
2 L
iquid
sCristobalite
Tridymite
1500
1400
1300
1200
1527
1251
1249
1144
1180
1157
1138
1143
1166
1194
weight percent
Tephroite
Rhodonite
1200
Ferrous Processing 17
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Phase vs. Phase diagram
Ferrous Processing 18
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2012
Phase vs. Phase diagram
[41] Osborn and Schairer
Liquid
Liquid + Mel
Mel
[22] Buddington : rxn time not enough
Liquid
Liquid + rare mel
mel + rare L
Geh-Aker (melilite solution)
Liquid
(75, 1390oC)
L+Merw
System Ca2Al2SiO7 - Ca2MgSi2O7
wt% Ca2MgSi2O7/(Ca2Al2SiO7+Ca2MgSi2O7)
T(o
C)
0 10 20 30 40 50 60 70 80 90 100
1200
1300
1400
1500
1600
1700
Melilite solid solution
Spinel solution
‘Coru’ solution
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2012
ilmenite Ti-spinel
Pseudo-brookite
Phase vs. Phase diagram
Ferrous Processing 20
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Montreal
2012
Phase vs. Phase diagram
Ferrous Processing 21
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2012
CaO
SiO2
Al2O3
Na2O
C2AS CA
CAS2
C2S
CS
NAS2 NAS6
C: CaO
A: Al2O3
N: Na2O
S: SiO2
NA
NA6
NS
Na2O containing system: Na2O-SiO2-CaO-Al2O3
Weill et al. (1980), compliation
Feldspar
Slag
CaAl2Si2O8 - NaAlSi3O8
mole NaAlSi3O8/(CaAl2Si2O8+NaAlSi3O8)
T(C
)
0 0.2 0.4 0.6 0.8 1
1000
1400
1800
* Most updated version: ‘CON1’ database
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2012
ASlag-liq
ASlag-liq + NaAlO2(s2)
NaAlO2(s2) + Na2Al12O19(s)
Na2O(s) + NaAlO2(s2)
Na2O(s2) + NaAlO2(s2)
Na2O(s3) + NaAlO2(s2)
NaAlO2(s2) + NaAl9O14(s)
ASlag-liq + NaAl9O14(s)
NaA
l 9O
14(s
) +
Al 2O
3(s
4)
Na2O - Al2O3
Al2O3/(Na2O+Al2O3) (mol/mol)
T(C
)
0 .2 .4 .6 .8 1
500
700
900
1100
1300
1500
1700
1900
2100
2300
2500
Ferrous Processing 23
Rys (2008): DTA-TG, heating
Rys (2008): DTA-TG, cooling
Na
10S
iO7
Na
4S
iO4
Na
2S
iO3
Na
6S
i 2O
7
Na
2S
i 2O
5
Na
6S
i 8O
19
Na2O mole fraction SiO2
Tem
pera
ture (
K)
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
700
900
1100
1300
1500
1700
1900
2100
Phase vs. Phase diagram: Na2O-Al2O3-SiO2 system
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2012
Phase vs. Phase diagram: Na2O-Al2O3-SiO2 system
NASh
Carg
Neph
NASl
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Moir and Glasser (1974)(1:2:3)
(1:2:3) + (2:1:3)
(1:2:3) + bCS
L + (1:2:3)
(2:1:3)
L + (2:1:3)
(2:1:3) + NS
aCS
aCS + (1:2:3)
aCS + bCS + (1:2:3)
L + aCS
bCS + (1:2:3)
aCS + bCS
L
L + NS
(1:2:3)' - maybe (1:1:2)
(1:2:3)' + NS
(1:2:3) + (2:1:3) + NS
Slag
1:2:3
1:2:3 + Na2SiO3(s)
Na2SiO3(s) + Na4CaSi3O9(s)
1:2:3 + CaSiO3(s)
1:2:3 + CaSiO3(s2)
Slag + CaSiO3(s2)
CaSiO3 - Na2SiO3
mole CaSiO3/(CaSiO3+Na2SiO3)
T(C
)
0 0.2 0.4 0.6 0.8 1
0
300
600
900
1200
1500
1800
0.2
0.4
0.6
0.8
0.20.40.60.8
0.2
0.4
0.6
0.8
SiO2
Na2O CaOWeight %
(a:b:c) = aNa2O.bCaO.cSiO2
(2:0:1)
(3:0:2)
(1:0:1)
(1:0:2)
(0:1:1)
(0:2:1)
(0:3:2)
(0:4:1)
(5:0:1)
(1:1:5)
(1:3:6)
(2:1:3) (1:2:3)
(2:1:3)
(1:0:1)
(0:1:1)
(0:0:1) - Tr.
(0:0:1) - Cr.
(0:3:2)
Morey and Bowen (1925)
(1:2:3)
(1:3:6)
(1:0:2)
(0:0:1) - Qz.
(4:3:5)
(1:1:1)
(1:2:2)
Segnit (1953)
(1:1:1)
(2:1:3)
(1:2:3)
(1:2:2)
(4:3:5)
(1:0:1)
(0:2:1)
(0:1:1)
(3:0:8)
Shahid and Glasser (1971)
(1:1:5)
(1:0:2)
(1:2:3)
(1:3:6)
(3:0:8)
(0:0:1) - Qz.
(0:0:1) - Tr.
1200 o C11
00
o C
1000
o C 1300
oC 1400
oC 1500
oC
1100
o C
SiO2 - CaO - Na2O
Phase vs. Phase diagram: Na2O-CaO-SiO2 system
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.10.20.30.40.50.60.70.80.9
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
SiO2
Na2O CaOmole fraction
(a:b:c) = aNa2O.bCaO.cSiO2
(2:0:1)
(3:0:2)
(1:0:1)
(1:0:2)
(0:1:1)
(0:2:1)
(0:3:2)
(0:4:1)
(5:0:1)
(1:1:5)
(1:3:6)
(2:1:3) (1:2:3)
(1:2:2)
(1:1:1)
(4:3:5)
(3:0:8)
CaO-Na2O-SiO2
FactSage
?
NCSO: 1:2:3 solid solution
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2012
Montreal
2012
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.10.20.30.40.50.60.70.80.90.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
Na2O
CaO Al2O3mole fraction
(a:b:c) = aNa2O.bCaO.cAl2O3
(0:1:1) (0:1:2) (0:1:6)
(1:8:3) (1:0:9)
(1:0:6)
(0:3:1)
(1:0:1)
CaO(s)
NaAlO2(s2)
1:1:2 NaAl9O14(s)
Al2O3(s4)CaAl2O4(s)CaAl4O7(s)
Na2O - Al2O3 - CaO
Projection (Slag)
FactSage
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.10.20.30.40.50.60.70.80.9
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
mole fraction
Slag
Na2O
CaO Al2O3mole fraction
N(a)C(b)A(c) = aNa2O.bCaO.cAl2O3
CA CA2 CA6
NC8A3 NA9NA6
C3A
NCA2s.s
NC3A8
NA
Verweij and Saris (1986), maximum solubility
Na2O - Al2O3 - CaO
1200oC
FactSage
Phase vs. Phase diagram: Na2O-Al2O3-CaO System
NCA2: (Na2,Ca)O·Na2O·2Al2O3 solid solution
Ferrous Processing 26
2011 Montreal Montreal
2012
Montreal
2012
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.10.20.30.40.50.60.70.80.9
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
MELCgNe
PW
Juan (1950)Ca2Al2SiO7
CaSiO3 NaAlSiO4mass fraction
Ca2Al2SiO7
CaSiO3 NaAlSiO4mass fraction
T(min) = 1162.95 oC, T(max) = 1594.98
oC
Melilite
CaSiO3(s2)
Ca3Si2O7(s)
Nepheline
Carnegieite
10/25/2008
D:\Work\CRCT\2007_MoldFlux_POSCO\Na2O-CaO-SiO2-Al2O3\quaternary_parameter\PD_CaSiO3-Ca2Al2SiO7-NaAlSiO4.emfCaO
SiO2
Al2O3
Na2O
Phase vs. Phase diagram: Na2O-Al2O3-SiO2-CaO System
Ferrous Processing 27
2011 Montreal Montreal
2012
Montreal
2012
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.10.20.30.40.50.60.70.80.9
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
CA2S2CgNeC3APWC2AS2b-A
Gummer (1943)CaAl2Si2O8
CaSiO3 NaAlSiO4mass fraction
CaAl2Si2O8
CaSiO3 NaAlSiO4mass fraction
T(min) = 1163.86 oC, T(max) = 1555
oC
Feldspar
CaSiO3(s2)
Melilite
Carnegieite
10/25/2008
D:\Work\CRCT\2007_MoldFlux_POSCO\Na2O-CaO-SiO2-Al2O3\quaternary_parameter\PD_CaSiO3-CaAl2Si2O8-NaAlSiO4.emfCaO
Al2O3
Na2O
SiO2
15
00
Phase vs. Phase diagram: Na2O-Al2O3-SiO2-CaO System
Ferrous Processing 28
2011 Montreal Montreal
2012
Montreal
2012
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.10.20.30.40.50.60.70.80.9
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1:2:32:1:3CgNePWNSW
Spivak (#1342)NaAlSiO4
CaSiO3 Na2SiO3mass fraction
NaAlSiO4
CaSiO3 Na2SiO3mass fraction
NaAlSiO4
CaSiO3 Na2SiO3mass fraction
NaAlSiO4
CaSiO3 Na2SiO3mass fraction
T(min) = 919.18 oC, T(max) = 1540.17
oC
Carnegieite
Nepheline
1:2:3
CaSiO3(s2)
2:1:3
Na2SiO3(s)
10/25/2008
D:\Work\CRCT\2007_MoldFlux_POSCO\Na2O-CaO-SiO2-Al2O3\quaternary_parameter\PD_NaAlSiO4-CaSiO3-Na2SiO3.emf
CaO
Al2O3
Na2O
SiO2
Phase vs. Phase diagram: Na2O-Al2O3-SiO2-CaO System
Ferrous Processing 29
2011 Montreal Montreal
2012
Montreal
2012
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.10.20.30.40.50.60.70.80.9
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
SiO2
Na2O CaOmass fractions /(SiO2+CaO+Na2O)
T(min) = 812.79 oC, T(max) = 2394.5
oC
CaO(s)
1:1:2 Ca2SiO4(s3)
Ca2SiO4(s2)Melilite
Ca3Si2O7(s)
1:2:3CaSiO3(s2)
Nepheline
Feldspar
Al6Si2O13(s)
Na2Ca3Si6O16(s)
Feldspar
NaAlO2-NaAlSiO41
NaAlO2-NaAlSiO4
NaAlO2-NaAlSiO41
SiO2 - CaO - Na2O - Al2O3
15wt% Al2O
3 section
SiO2
CaO
Al2O3
Na2O
1400
1300
1200
1100
Phase vs. Phase diagram: Na2O-Al2O3-SiO2-CaO System
Ferrous Processing 30
2011 Montreal Montreal
2012
Montreal
2012 Ferrous Processing 31
Simple examples of Equilib
Target/Transition, Stream, Heat balance, Open,
Fixing partial pressure, Fe saturation, etc.
2011 Montreal Montreal
2012
Fe-LIQUID
Si(s) + FeSi2(s)
Si(s) + Fe3Si7(s)
Fe-LIQUID + Si(s)Fe-LIQUID + FeSi(s)
BCC_A2
FCC(c,n)
BCC_B2
FeSi(s) + Fe5Si3(s)
FeSi(s) + Fe2Si(s)
Fe - Si
mass 100Si/(Fe+Si)
T(C
)
0 20 40 60 80 100
200
400
600
800
1000
1200
1400
1600
1800
1030°C
5wt%Si
Fe-Si binary phase diagram - Fe-5wt.% Si at 1030 oC
Ferrous Processing 32
2011 Montreal Montreal
2012
Reactants Window - Fe-Si at Fe-5wt.% Si
Reactants Window
Data Search
Ferrous Processing 33
2011 Montreal Montreal
2012
Selection of solid phases
Pure solids
Menu Window - Fe-5wt.% Si at 1030 oC
Ferrous Processing 34
2011 Montreal Montreal
2012
Montreal
2012
Results Window - Fe-5wt.% Si at 1030 oC
Ferrous Processing 35
2011 Montreal Montreal
2012
Menu
Fe-5wt.% Si from 200 oC
to 1800 oC every 200 oC
Fe-5wt.% Si transition calculations
Ferrous Processing 36
2011 Montreal Montreal
2012
Fe-5wt.% Si formation target for liquid phase
F – formation target phase
Ferrous Processing 37
2011 Montreal Montreal
2012
Fe-5wt.% Si precipitate target for liquid phase
P – precipitate target phase
Ferrous Processing 38
2011 Montreal Montreal
2012
Montreal
2012
Creating new stream : Fe-0.1C-1Mn-1Si at 1600oC
Ferrous Processing 39
2011 Montreal Montreal
2012
Montreal
2012
Save the liquid FeLQ
phase as a stream
Creating new stream : Fe-0.1C-1Mn-1Si at 1600oC
Ferrous Processing 40
2011 Montreal Montreal
2012
Montreal
2012
Import stream : Fe-0.1C-1Mn-1Si at 1600oC
Ferrous Processing 41
2011 Montreal Montreal
2012
Montreal
2012
Heat balance: Fe-0.1C-1Mn-1Si(1600oC) + Al (25oC)
Adiabatic calculation :
Delta(H) = 0
Calculated adiabatic
temperature = 1605.5 oC
Ferrous Processing 42
2011 Montreal Montreal
2012
Montreal
2012
RH – Vacuum degassing process
Open Calculation - off-gas removal
Stream Fe-0.1C-1Mn-1Si + O2
at 1600oC and 0.01 atm
Ferrous Processing 43
2011 Montreal Montreal
2012
Montreal
2012
Carbon content decreases due
to the reactions:
C + O2 = CO2
C + 0.5O2 = CO
New slag formed due to Si and
Mn oxidation:
Mn + 0.5O2 = MnO
Si + O2 = SiO2
Open Calculation - results
Ferrous Processing 44
2011 Montreal Montreal
2012
Montreal
2012
1
2
3
Open Calculation - plot of log(wt% liquid steel)
Ferrous Processing 45
2011 Montreal Montreal
2012
Montreal
2012
Fe_FeLQ Fe_FeLQ Fe_FeLQ Fe_FeLQ
Mn_FeLQ Mn_FeLQ Mn_FeLQ Mn_FeLQSi_FeLQ Si_FeLQSi_FeLQ
Si_FeLQ
O_FeLQ O_FeLQ O_FeLQ O_FeLQ
C_FeLQ C_FeLQ C_FeLQ C_FeLQ
100% [FTmisc-FeLQ_Fe-liq] + <A> O2
c:\FactSage\casestudy\Equi0.res 21May09
- page -
log
10(w
eig
ht
%)
1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00
-4.00
-3.00
-2.00
-1.00
0
1.00
2.00
Open Calculation - log(wt%) vs page
Ferrous Processing 46
2011 Montreal Montreal
2012
Montreal
2012
Fixed pO2 in Fe-Cr-O2
2
Specify the activity of the selected
species or set a range of activities
(linear or log scale)
Fixed activity of gas and solid species
3
1
Ferrous Processing 47
2011 Montreal Montreal
2012
Montreal
2012
Results at log(pO2) = -20
Small amount of Cr2O3
can form on top of the
Fe-20%Cr alloy
Fixed partial pressure of a gas : O2
Ferrous Processing 48
2011 Montreal Montreal
2012
Montreal
2012
Fixed partial pressure of a gas : O2
Fixed pO2 in MgO-FetO-SiO2 slag
Ferrous Processing 49
2011 Montreal Montreal
2012
Montreal
2012
Results at log(pO2) = -10
Results at log(pO2) = -2
The amounts of FeO and Fe2O3 change with PO2
Fixed partial pressure of a gas : O2
Results at log(pO2) = -15
Ferrous Processing 50
2011 Montreal Montreal
2012
Montreal
2012
Fixed activity of Fe: Fe saturation
Slag (CaO-MgO-SiO2) and liquid Fe equilibration at 1600oC
One way to fix Fe saturation in steelmaking
calculations is to add a small amount of Fe as
an input component
Ferrous Processing 51
2011 Montreal Montreal
2012
Montreal
2012
Gas / Slag (CaO-MgO-FeO-SiO2) / Liquid Fe equilibration
Fixed partial pressure of a gas : Fe saturation and fixed SO2
Ferrous Processing 52
2011 Montreal Montreal
2012
Montreal
2012
Gas (SO2, S2, O2, etc.)
Slag (CaO, MgO, FeO, …
CaS, MgS, FeS, etc.)
Fe-Lq (O, S, etc.)
Equilibration reactions include:
CaO + SO2 = CaS + 2O
SO2 = 2O + S
CaO + FeS = CaS + FeO
……
Fixed partial pressure of a gas : Fe saturation and SO2
Ferrous Processing 53
2011 Montreal Montreal
2012
Montreal
2012
Composition Target: slag / liquid steel equilibrium
“ How to calculate optimum amount of CaSi to reduce S
in liquid steel to a targeted composition”
Composition target: target S content in liquid steel
Ferrous Processing 54
2011 Montreal Montreal
2012
Montreal
2012
Add CaSi (<A>) to reduce [%S] in Fe-LIQUID to 0.002%.
Composition target: target S content in liquid steel
Ferrous Processing 55
2011 Montreal Montreal
2012
Montreal
2012
Composition target: target S content in liquid steel
Amount of CaSi = 0.96 gram to obtain [%S] = 0.002%
Ferrous Processing 56
2011 Montreal Montreal
2012
Fe-0.01C-0.01N-0.03Nb-0.07Ti-0.5Mn: three possible FCC phases
J option for FCC phase: Fe steel containing (Ti,Nb)(C,N) ppts
Ferrous Processing 57
2011 Montreal Montreal
2012
FCC#1 FCC#1 FCC#1 FCC#1 FCC#1
FCC#3 FCC#3 FCC#3 FCC#3 FCC#3
99.39 Fe + 0.01 C + 0.01 N + 0.03 Nb +
T(C)
log
10(g
ram
)
0800 1000 1200 1400
-03
-01
01
03
Austenite, Ti and Nb carbo-nitrides are all FCC. In the
FSStel database, all these fcc phases are modeled as a
single FCC_A1 solution with three possible miscibility gaps.
J option for FCC phase: Fe steel containing (Ti,Nb)(C,N) ppts
Ferrous Processing 58
2011 Montreal Montreal
2012
Montreal
2012
AlNMnS
M7C3
Cementite
Temperature, oC
ph
ase
fra
cti
on
(w
eig
ht
percen
t)
500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600
0.0
0.2
0.4
0.6
0.8
1.0
FCC
BCC
Liquid
Cementite
Temperature, oC
ph
ase
fra
cti
on
(w
eig
ht
percen
t)500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600
0
10
20
30
40
50
60
70
80
90
100
Precipitation of AlN and MnS in a commercial Si-steel
Fe-0.054C-3.2Si-0.1Mn-0.028Al-0.015X-0.007S-0.0075N-0.05X-0.2X (wt%): Oriented Si-Steel
2nd recrystallization temp (pinning)
Ferrous Processing 59
2011 Montreal Montreal
2012
Montreal
2012
Phase diagram / Phase fraction of 430 Stainless Steel
BCC
FCC
M23C
SIGMA
Liquid
Temperature, (oC)
ph
ase
dis
trib
uti
on
, w
t%
500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600
0
10
20
30
40
50
60
70
80
90
100
Liquid
BCC
L+BCC
BCC+FCC
BCC + FCC + M23C6
BCC + M23C6
SIGMA + BCC + M23C6
wt% C
Tem
per
atu
re,
oC
0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10
500
600
700
800
900
1000
1100
1200
1300
1400
1500
1600
1700
1800
Fe-16.2Cr-0.06C-0.3Si-0.4Mn-0.3Ni-0.015X(wt%): STS430
Ferrous Processing 60
2011 Montreal Montreal
2012
Montreal
2012 Ferrous Processing 61
Simple examples of Phase diagram
Binary phase diagram
Ternary and multi-component systems
2011 Montreal Montreal
2012
Montreal
2012
There is a stable miscibility gap in slag; automatic selection by FactSage
Binary phase diagram: CaO-SiO2
Ferrous Processing 62
2011 Montreal Montreal
2012
Montreal
2012
ASlag-liq
ASlag-liq + ASlag-liq#2
ASlag-liq + SiO2(s6)
SiO2(s4) + CaSiO3(s2)
Ca2SiO4(s3) + CaO(s)
Ca3SiO5(s) + CaO(s)
CaO(s) + Ca2SiO4(s2)
ASlag-liq + Ca2SiO4(s3)
ASlag-liq + CaSiO3(s2)
CaO - SiO2
mass 100SiO2/(CaO+SiO2)
T(C
)
0 20 40 60 80 100
1000
1200
1400
1600
1800
2000
There is a stable miscibility gap in slag.
Binary phase diagram: CaO-SiO2
Ferrous Processing 63
2011 Montreal Montreal
2012
Montreal
2012
Ternary phase diagram: CaO-SiO2-Al2O3 isothermal section
Ferrous Processing 64
2011 Montreal Montreal
2012
Montreal
2012
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.10.20.30.40.50.60.70.80.9
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
SiO2
CaO Al2O3mass fraction
ASlag-liq
ASlag-liq + SiO2(s6)
ASlag-liq + Mullite
ASlag-liq + Al2O3(s4)
ASlag-liq + CaO(s)
ASlag-liq + Ca2SiO4(s3)
CaO - SiO2 - Al2O3
1550oC
FactSage
Ternary phase diagram: CaO-SiO2-Al2O3 isothermal section
Ferrous Processing 65
2011 Montreal Montreal
2012
Montreal
2012
SiO2
CaO Al2O3
1:1
Ternary system: section in ternary (isopleth)
Ferrous Processing 66
2011 Montreal Montreal
2012
Montreal
2012
ASlag-liq
ASlag-liq + Al2O3(s4)
ASlag-liq + CaAl12O19(s)
ASlag-liq + Ca2Al2SiO7(s)
ASlag-liq + CaSiO3(s2)
CaO - SiO2 - Al2O3
mass (CaO-SiO2)/(CaO+SiO
2+Al
2O
3) = 0
mass 100Al2O3/(CaO+SiO2+Al2O3)
T(C
)
0 20 40 60 80 100
1000
1160
1320
1480
1640
1800
CaO-SiO2-Al2O3 Vertical section at
(wt%CaO/wt%SiO2 ) = 1
Ternary system: section in ternary (isopleth)
Ferrous Processing 67
2011 Montreal Montreal
2012
Montreal
2012
Oxidation diagram: Fe-Cr-O2
Combination of many databases:
FACT53: gases (if necessary)
FToxid: oxide phases
FSStel: fcc, bcc and other metallic phases
Ferrous Processing 68
2011 Montreal Montreal
2012
Montreal
2012
Log pO2 for y-axis variable
ASpinelASlag-liq + ASpinel
Fe-LIQUIDBCC_A2
Fe-LIQUID + M2O3(corundum)
M2O3(corundum) + ASpinel
Fe-LIQUID + ASpinel
Fe - Cr - O2
1600oC
mole Cr/(Fe+Cr)
log
10(p
(O2))
(atm
)
0 0.2 0.4 0.6 0.8 1
-20
-17
-14
-11
-8
-5
Oxidation diagram: Fe-Cr-O2
Ferrous Processing 69
2011 Montreal Montreal
2012
Montreal
2012
Predominance diagram: Fe-Mn-O2-S2
Combination of many databases:
FACT53: gases (if necessary)
FToxid: oxide phases
FSStel: fcc, bcc and other metallic phases
Ferrous Processing 70
2011 Montreal Montreal
2012
Montreal
2012
ASlag-liq
FCC(c,n) + MnS(s)
BMonoxide + FCC(c,n)
FCC(c,n)
ASlag-liq + FCC(c,n)
ASlag-liq + Fe-LIQUID
BMonoxide
BSpinel
BMonoxide + BSpinel
MnSO4(s) + FeSO4(s)
BSpinel + MnSO4(s)
O2 - S2 - Fe - Mn
1300oC, mass Mn/(Fe+Mn) = 0.3
log10(p(S2)) (atm)
log
10(p
(O2))
(atm
)
-20 -16 -12 -8 -4 0
-20
-16
-12
-8
-4
0
Predominance diagram: Fe-Mn-O2-S2
Ferrous Processing 71
2011 Montreal Montreal
2012
Montreal
2012
This is NOT 10% Al2O3 section !!
Quaternary diagram: iso-composition section
Ferrous Processing 72
2011 Montreal Montreal
2012
Montreal
2012
How to calculate 10% section exactly ?
CaO+MgO+SiO2 = 1.0 (100%), Al2O3 should be 10%
CaO+MgO+SiO2 = 1.0, Al2O3 = x
x/(1+x) = 0.1 (=10%)
x = 0.11111
So, if we give Al2O3 = 0.11111 Al2O3 = 10%
2) Click here
= 10% Al2O3
This is 10% Al2O3 section !!
1) Equilib calculation mode
Quaternary diagram: iso-composition section
Ferrous Processing 73
2011 Montreal Montreal
2012
Montreal
2012
Quaternary system: CaO-Ca2SiO4-MgAl2O4
Ferrous Processing 74
2011 Montreal Montreal
2012
Montreal
2012
Liquid
FeS
i 2
BCC
FCC
FeS
i
Fe
3Si 7
Fe
5S
i 3
Fe
2S
i
Si
weight percent Si
Tem
pera
ture, o
C
0 10 20 30 40 50 60 70 80 90 100
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1400
1500
1600
1700
1800
Alloy Design: Electric steel (Si-steel)
Phase diagram of Fe-Si system
Ferrous Processing 75
2011 Montreal Montreal
2012
Montreal
2012
BCC
BCC + Fe3C
FCC
LIQUID
FCC+BCC
Fe - C - Si
C = 25 ppm
wt% Si
Tem
per
atu
re,
oC
0 1 2 3 4 5 6
500
600
700
800
900
1000
1100
1200
1300
1400
1500
Alloy Design: Electric steel (Si-steel)
Alloy Design: Fe-Si + C
Ferrous Processing 76
2011 Montreal Montreal
2012
Montreal
2012
BCCFCC
BCC+Cementite
0.05% C
0.03% C
0.01% C
No Carbon
weight percent Si
Tem
pera
ture, o
C
0 1 2 3 4 5 6 7 8 9 10
700
800
900
1000
1100
1200
1300
1400
1500Alloy Design: Fe-Si + C
Alloy Design: Electric steel (Si-steel)
Ferrous Processing 77
2011 Montreal Montreal
2012
Montreal
2012
BCCFCC
0.1% Mn
Fe-Si, Fe-Si-0.03Al
weight percent Si
Tem
pera
ture, o
C
0 1 2 3 4 5
700
800
900
1000
1100
1200
1300
1400
1500
Alloy Design: Fe-Si + Al, Mn
Alloy Design: Electric steel (Si-steel)
Ferrous Processing 78
2011 Montreal Montreal
2012
Montreal
2012
FCC + SiO2(Trid)
Mono + Fe2SiO4Spinel + Fe2SiO4
Spinel + SiO2(Trid)
SiO2(Trid) + Fe2O3
Fe2O3 + SiO2(Quar)
Mono + Slag
Spinel + Slag
BCC
BCC + SiO2(Trid)
FCC + Slag
FCC + Fe2SiO4
BCC + Fe2SiO4
BCC + SiO2(Quar)
BCC + SiO2(Trid)
Spinel + SiO2(Quar)
Temperature, oC
log
10(p
(O2))
(a
tm)
800 900 1000 1100 1200 1300
-20
-17
-14
-11
-8
-5
Mono = MgO-FeO solutions
Formation of base coating on the surface of a commercial Si steel
Ferrous Processing 79
2011 Montreal Montreal
2012
Montreal
2012 Ferrous Processing 80
Application: Activity calculations
Slag: binary, ternary and multi-component systems
FeLq : oxygen and alloying elements
2011 Montreal Montreal
2012
Activity calculations – Binary system
Ferrous Processing 81
2011 Montreal Montreal
2012
Montreal
2012
Activity calculations – Binary system
Activity of solid or liquid standard state) ?
Ferrous Processing 82
2011 Montreal Montreal
2012
Montreal
2012
Activity calculations – Ternary system
Calculation of iso-activity line of SiO2
in the CaO-MgO-SiO2 system
Ferrous Processing 83
2011 Montreal Montreal
2012
Montreal
2012
Activity calculations – Ternary system
Save results in excel
or spread sheet form
Ferrous Processing 84
2011 Montreal Montreal
2012
Montreal
2012
Activity calculations – Ternary system
Plot the results in triangle diagram
- Prepare the triangle frame
- Plot the A,B,C coordinate numbers in triangle diagram
Ferrous Processing 85
2011 Montreal Montreal
2012
Montreal
2012
Activity calculations – Quaternary or higher order system
Composition of Al2O3 is NOT 0.1
Impossible to calculate iso-activity line of
A with fixed B composition in quaternary
A-B-C-D system yet.
Ferrous Processing 86
2011 Montreal Montreal
2012
Montreal
2012
Activity calculations – Quaternary or higher order system
A. Draw phase diagram of A-B-C with fixed D, and Check the iso activity point
manually of A in phase diagram mode
B. Calculate activity of A in entire A-B-C with fixed D section and manually connect
iso-activity of A.
In future, iso-activity calculation mode will be added into Phase Diagram module.
Ferrous Processing 87
2011 Montreal Montreal
2012
Montreal
2012
Activity of oxygen (wt% standard state) in liquid steel
Log aO(wt%) = Log(aO in FeLq) - Log((EXP(-15280/T+3.5)*55.847/100/16))
where T in Kelvin
)state.stdHenrian(aM
M100)state.std%wt(a i
Fe
ii
.).(.).(
)()(
lnln
ln
SSElementpureMssHenrianM
oS.S.ElementurePM
oS.S.HenrianM
oM
aaRT
ggγRT
5.3/15280ln TγoO
Reference pure element standard state of O in FeLq : Gas (0.5 O2)
aO in FeLq
: value used in FeLq database; slightly different
depending on assessments
Ferrous Processing 88
2011 Montreal Montreal
2012
Montreal
2012
Activity of oxygen (wt% standard state) in liquid steel
aO in FeLq
Total dissolved Al and O
Dissolved Al, O, Al*O, Al2*O
Ferrous Processing 89
2011 Montreal Montreal
2012
Montreal
2012
aO in FeLQ Total dissolved Al and O
Dissolved
unassociated O
Activity of oxygen (wt% standard state) in liquid steel
Then, convert aO in FeLq to aO wt% s.s.
Ferrous Processing 90
2011 Montreal Montreal
2012
Montreal
2012 Ferrous Processing 91
Application: Addition of new component in slag
V2O3 into molten slag for V distribution calculations
(Henrian Solution)
2011 Montreal Montreal
2012
Montreal
2012
New component in slag: Henrian activity coefficient
V2O3 containing slag // Liquid Fe-Al steel
All V go to liquid Fe ??
(because no V oxide in slag yet)
Ferrous Processing 92
2011 Montreal Montreal
2012
Montreal
2012
New component in slag: Henrian activity coefficient
Setting activity coefficient
of V2O3 in slag
Ferrous Processing 93
2011 Montreal Montreal
2012
Montreal
2012
New component in slag: Henrian activity coefficient
Ferrous Processing 94
2011 Montreal Montreal
2012
Montreal
2012
New component in slag: Henrian activity coefficient
V in FeLq = 0.577 wt%
V2O3 in slag = 0.134 wt%
The distribution of V between slag and metal can
be varied depending on the activity coefficient.
(evaluated from experimental data)
Ferrous Processing 95
2011 Montreal Montreal
2012
Montreal
2012 Ferrous Processing 96
Application: Addition of new compound and
solution (user defined) in calculations
MnCr2O4-MnAl2O4 ideal solid solution
• New stainless steel production: high
Mn stainless steel 400 grade. High
MnO formation in AOD / VOD refining
process
• MnCr2O4-MnAl2O4 inclusion
formation in Mn and Cr containing
steels
2011 Montreal Montreal
2012
Montreal
2012
User Compound Database
(2) Select “mixer”
(1) Type the compounds
(3): add the MnO and Cr2O3 from known database
(4): select your own database (INHOBASE) and copy the result
Creating user compound database: MnCr2O4 from MnO and Cr2O3
Ferrous Processing 97
2011 Montreal Montreal
2012
Montreal
2012
User Compound Database
Go(cubic-MnCr2O4) = Go(MnO) + Go(Cr2O3) + Hf − TSf
Hf = -51 kJ/mol, S = 0 J/mol-K
Before Hf and Sf
after Hf and Sf
Ferrous Processing 98
2011 Montreal Montreal
2012
Montreal
2012
User Compound Database
Add H298, S298 and Cp, respectively
Creating user compound database:
MgCr2O4 from H298, S298 and Cp
Ferrous Processing 99
2011 Montreal Montreal
2012
Montreal
2012
Ideal Solution between compounds
Database registeration
Priority of database
Ferrous Processing 100
2011 Montreal Montreal
2012
Montreal
2012
Ideal Solution between compounds
MnCr2O4-MgCr2O4 ideal sol’n: (Mg,Mn)Cr2O4
Both MnCr2O4 and MgCr2O4 are selected as
ideal solution #1 with 0 activity coefficients
Ferrous Processing 101
2011 Montreal Montreal
2012
Montreal
2012
Ideal solution between compounds
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.10.20.30.40.50.60.70.80.9
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
SiO2
CaO Cr2O3mass fractions /(CaO+SiO2+Cr2O3)
Liqiud
Liquid + Ideal #1
O2 - CaO - SiO2 - Cr2O3 - MnO - MgO1700
oC, p(O
2) = 10
-11 atm, MnO/Z (g/g) = 0.1,
MgO/Z (g/g) = 0.05, Z=(CaO+SiO2+Cr
2O
3)
Ideal solution of
MgCr2O4-MnCr2O4
Ferrous Processing 102
2011 Montreal Montreal
2012
Montreal
2012 Ferrous Processing 103
Application: Advanced Phase diagram
calculations
Fe oxide and Fe saturation
Multi-component phase diagrams
Slag – Refractories / Slag – Inclusions
2011 Montreal Montreal
2012
Montreal
2012
Fe oxide containing system: Fe saturation
Intentional addition of Fe to make Fe saturation
Ferrous Processing 104
2011 Montreal Montreal
2012
Montreal
2012
Fe oxide containing system: Fe saturation
ASlag-liq + Fe(liq)
ASlag-liq + Fe(s)
ASlag-liq + Fe(s2)
AMonoxide + Fe(s2) + Fe2SiO4(s)
AMonoxide + Fe(s) + Fe2SiO4(s)
Fe(s) + FeO(s) + Fe2SiO4(s)ASpinel + Fe(s) + Fe2SiO4(s) Fe(s) + SiO2(s) + Fe2SiO4(s)
Fe(s) + SiO2(s2) + Fe2SiO4(s)
Fe(s) + SiO2(s4) + Fe2SiO4(s)
Fe(s2) + SiO2(s4) + Fe2SiO4(s)
ASlag-liq + Fe(s2) + SiO2(s4)
ASlag-liq + Fe(s) + SiO2(s4)
ASlag-liq + Fe(s) + SiO2(s6)
ASlag-liq + Fe(liq) + SiO2(s6)
ASlag-liq + ASlag-liq#2 + Fe(liq)
ASlag-liq + AMonoxide + Fe(s2)
Fe(s) + FeO(s) + Fe2SiO4(s)
FeO - SiO2 - Fe
Fe/(FeO+SiO2) (g/g) = 0.001
SiO2/(FeO+SiO2) (g/g)
T(C
)
0 0.2 0.4 0.6 0.8 1
500
700
900
1100
1300
1500
1700
1900
Monoxide = FeO. But due to slightly
different Gibbs energies of FeO stored in
two databases, FeO from FACT53
appears in the calculation. for better
calcs, remove FeO(s) from database
selection
Intentional addition of Fe
to make Fe saturation
Ferrous Processing 105
2011 Montreal Montreal
2012
Montreal
2012
Fe oxide containing system: fixed PO2
Fixing PO2 to control the
oxidation state of Fe
Ferrous Processing 106
2011 Montreal Montreal
2012
Montreal
2012
Fe oxide containing system: fixed PO2
Fe2O3(s) + SiO2(s2)
ASpinel + SiO2(s2)
ASpinel + SiO2(s4)
Fe2SiO4(s) + SiO2(s4)
ASlag-liq + SiO2(s4)
ASlag-liq
ASlag-liq + AMonoxide
Fe(liq) + SiO2(s6)
ASlag-liq + Fe(liq)
FeO - SiO2 - O2
p(O2) = 10
-10 atm
SiO2/(FeO+SiO2) (g/g)
T(C
)
0 0.2 0.4 0.6 0.8 1
500
700
900
1100
1300
1500
1700
1900
When PO2 is fixed with selection of Fe, slag and
Fe oxides can be reduced by Oxygen to Fe at
certain temperature and composition
Ferrous Processing 107
2011 Montreal Montreal
2012
Montreal
2012
Fe oxide containing system: fixed CO/CO2 gas
Select only CO, CO2 and O2 gas to simulate real experiment of oxide/gas equilibration.
If we select all gases, some amount of oxides can be evaporated depending on the relative amount
of gas and oxide in the calculations
Fixing PO2 by CO/CO2 gas mixture
Ferrous Processing 108
2011 Montreal Montreal
2012
Montreal
2012
Fe oxide containing system: fixed CO/CO2 gas
gas_ideal + ASlag-liq
gas_ideal + ASlag-liq + SiO2(s6)
gas_ideal + ASlag-liq + SiO2(s4)
gas_ideal + ASlag-liq + Fe(s2) + SiO2(s4)
gas_ideal + Fe(s2) + SiO2(s4) + Fe2SiO4(s)
gas_ideal + Fe(s) + SiO2(s2) + Fe2SiO4(s)gas_ideal + Fe(s) + Fe2SiO4(s)
gas_ideal + AMonoxide + Fe(s2) + Fe2SiO4(s)
gas_ideal + AMonoxide + Fe(s) + Fe2SiO4(s)
gas_ideal + ASlag-liq + AMonoxide + Fe(s2)
gas_ideal + ASlag-liq + Fe(s2)
gas_ideal + ASlag-liq + Fe(s)
gas_ideal + ASlag-liq + Fe(liq)gas_ideal + ASlag-liq + ASlag-liq#2
gas_ideal + Fe(s) + SiO2(s2)
FeO - SiO2 - CO - CO2
CO/(FeO+SiO2) (mol/mol) = 0.9,
CO2/(FeO+SiO
2) (mol/mol) = 0.1
SiO2/(FeO+SiO2) (mol/mol)
T(C
)
0 0.2 0.4 0.6 0.8 1
500
700
900
1100
1300
1500
1700
1900
Fixing CO/CO2 ratio
Ferrous Processing 109
2011 Montreal Montreal
2012
Montreal
2012
Fe oxide containing system: fixed CO/CO2 gas
Ferrous Processing 110
2011 Montreal Montreal
2012
Montreal
2012
Fe oxide containing system: fixed CO/CO2 gas
gas_ideal + ASlag-liq
gas_ideal + ASpinel
gas_ideal + ASpinel + AMonoxide
gas_ideal + AMonoxide
gas_ideal + ASpinel + Fe2O3(s)
gas_ideal + ASpinel + C(s)
ASpinel + FeCO3(s) + C(s)
gas_ideal + FeCO3(s) + Fe2O3(s)
gas_ideal + ASlag-liq + ASpinel
Fe2O3 - CO - CO2
Fe2O
3/(CO+CO
2) (mol/mol) = 1
CO/(CO+CO2) (mol/mol)
T(C
)
0 0.2 0.4 0.6 0.8 1
0
200
400
600
800
1000
1200
1400
1600
1800
2000
gas_ideal + ASlag-liq
gas_ideal + AMonoxide
gas_ideal + ASpinel + C(s)
gas_ideal + FeCO3(s) + C(s)
gas_ideal + BCC_A2 + AMonoxide
gas_ideal + FCC_A1 + AMonoxide
gas_ideal + LIQUID + ASlag-liq
gas_ideal + BCC_A2 + ASlag-liq
gas_ideal + ASpinel
gas_ideal + FeCO3(s) + Fe2O3(s)
gas_ideal + ASpinel + Fe2O3(s)
gas_ideal + ASpinel + AMonoxide
Fe2O3 - CO - CO2
Fe2O
3/(CO+CO
2) (mol/mol) = 0.1
5/3/2011
C:\Workshop\Fe2O3-CO-CO2-large-Gas.wmf
CO/(CO+CO2) (mol/mol)
T(C
)
0 0.2 0.4 0.6 0.8 1
0
200
400
600
800
1000
1200
1400
1600
1800
2000
1mole
Fe2O3
1mole
CO-CO2 gas
<Closed system>
1mole
Fe2O3
10mole
CO-CO2 gas <Closed system>
1mole
Fe2O3
10mole CO-CO2 gas
<Open system>
Ferrous Processing 111
2011 Montreal Montreal
2012
Montreal
2012
CaO-FetO-SiO2 system with Fe saturation
Ferrous Processing 112
2011 Montreal Montreal
2012
Montreal
2012
CaO-FetO-SiO2 system with Fe saturation
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.10.20.30.40.50.60.70.80.9
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
SiO2
CaO FeOmass fractions /(CaO+FeO+SiO2)
ASlag-liq + Fe(liq)
ASlag-liq + AMonoxide + Fe(liq)
ASlag-liq + a-Ca2SiO4 + Fe(liq)
ASlag-liq + Fe(liq) + SiO2(s6)
ASlag-liq + AMonoxide + a-Ca2SiO4 + Fe(liq)
CaO - FeO - SiO2 - Fe
1650oC, Fe/(CaO+FeO+SiO
2) (g/g) = 0.001
Ferrous Processing 113
2011 Montreal Montreal
2012
Montreal
2012
CaO-FetO-SiO2-5wt%MgO system with Fe saturation
In FactSage phase diagram module, special
attention is required for the axis setting of
quaternary or higher order system.
The first three components are Always used as
A,B,C axis with 100% (1mole) base.
Therefore, for 5% MgO section, we have to set the MgO content as 0.05263 instead of 0.05
For x MgO section: y/(1+y) = x ‘y’ = x(1-x) : ‘y’ is the value for FactSage
Ferrous Processing 114
2011 Montreal Montreal
2012
Montreal
2012
CaO-FetO-SiO2-5wt%MgO system with Fe saturation
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.10.20.30.40.50.60.70.80.9
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
SiO2
CaO FeOmass fractions /(CaO+FeO+SiO2)
ASlag-liq + Fe(liq)
ASlag-liq + AMonoxide + Fe(liq)
ASlag-liq + a-Ca2SiO4 + Fe(liq)
ASlag-liq + AMonoxide + AMonoxide#2 + Fe(liq)
ASlag-liq + Fe(liq) + SiO2(s6)
CaO - FeO - SiO2 - MgO - Fe1650
oC, MgO/Z (g/g) = 0.05263, Fe/Z (g/g) = 0.001,
Z=(CaO+FeO+SiO2)
MgO saturation (MgO-FeO)
C2S saturation
BOF slag composition 5 wt% MgO section
Ferrous Processing 115
2011 Montreal Montreal
2012
CaF
2 = 0
%
10%
Liquid (L)
L +
Ca
O
2 Liquids
20%
L +
Ca
2S
iO4
L +
Ca
3S
iO5
wt% SiO2
wt%
Al 2
O3
0 10 20 30 40 50 60 70 80 90 1000
10
20
30
CaO-SiO2-Al2O3 + F slags for refining flux
CaO-Al2O3-SiO2 with various CaF2 content at 1650oC.
At 20% CaF2: Slag can directly equilibrated with CaO (no Ca2SiO4)
Using ‘CON1’ database
Change of Ca2SiO4 saturation
composition with CaF2 content
Ferrous Processing 116
2011 Montreal Montreal
2012
Montreal
2012
CaO-Al2O2-SiO2 slag – MgAl2O4 refractory
50%CaO-30%SiO2-20%Al2O3 slag in mole: (CaO)0.5618(SiO2)0.3146(Al2O3)0.1236
(Equilib or Phase Diagram’s components are in molar base)
ASlag-liq
ASlag-liq + ASpinel
ASlag-liq + ASpinel + MeliliteASlag-liq + Melilite
ASlag-liq + a-Ca2SiO4
ASlag-liq + CaSiO3(s2)
(CaO)0.5618(SiO2)0.3146(SiO2)0.1236 - MgAl2O4
MgAl2O4/((CaO)0.5618(SiO2)0.3146(SiO2)0.1236+MgAl2O4) (g/g)
T(C
)
0 0.2 0.4 0.6 0.8 1
1300
1400
1500
1600
1700
1800
Dissolution of spinel
inclusion into slag
Ferrous Processing 117
2011 Montreal Montreal
2012
Montreal
2012
CaO-Al2O2-SiO2 slag – MgAl2O4/Al2O3 refractories
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.10.20.30.40.50.60.70.80.9
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
(CaO)0.5618(SiO2)0.3146(SiO2)0.1236
Al2O3 MgAl2O4mass fraction
ASlag-liq
ASlag-liq + ASpinel
ASlag-liq + CaMg2Al16O27(s)
ASlag-liq + Ca2Mg2Al28O46(s)
ASlag-liq + CaAl12O19(s)
ASlag-liq + ASpinel + CaMg2Al16O27(s)
(CaO)0.5618(SiO2)0.3146(SiO2)0.1236 - MgAl2O4 - Al2O3
1600oC
High Alumina (MgAl2O4-Al2O3)
Refractories dissolution into slags
Ferrous Processing 118
2011 Montreal Montreal
2012
Montreal
2012
CaO-Al2O2-SiO2 slag – MgAl2O4/MgO refractories
ASlag-liq + a-Ca2SiO4
ASlag-liq
ASlag-liq + AMonoxide
ASlag-liq + ASpinel
ASlag-liq + ASpinel + AMonoxide
ASlag-liq + AMonoxide + a-Ca2SiO4
(CaO)0.5618(SiO2)0.3146(SiO2)0.1236 - MgAl2O4 - MgO
1600oC
MgO/((CaO)0.5618(SiO2)0.3146(SiO2)0.1236+MgAl2O4+MgO) (g/g)
MgA
l 2O
4/(
(CaO
) 0.5
61
8(S
iO2) 0
.31
46(S
iO2) 0
.12
36+
MgA
l 2O
4+
MgO
) (g
/g)
0 0.1 0.2 0.3 0.4 0.5
0
0.1
0.2
0.3
0.4
0.5
Ferrous Processing 119
2011 Montreal Montreal
2012
Montreal
2012
Phase diagram: Refractories design
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.10.20.30.40.50.60.70.80.9
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
(CaO)0.535(SiO2)0.25(Al2O3)0.05(MgO)0.1
MgTi2O4 MgAl2O4mass fraction
ASlag-liq + ASlag-liq#2
ASlag-liq
ASlag-liq + MgAl2O4(s)
ASlag-liq + ASlag-liq#2 + MgAl2O4(s)
ASlag-liq + ASlag-liq#2 + a-Ca2SiO4
ASlag-liq
ASlag-liq + MgAl2O4(s)
(CaO)0.535(SiO2)0.25(Al2O3)0.05(MgO)0.1 - MgAl2O4 - MgTi2O4 - Fe
1700oC, a(Fe(liq)) = 0.7943
Ferrous Processing 120
Dissolution of MgAl2O4/MgTi2O4
refractories into slag
MgAl2O4 saturation line
2011 Montreal Montreal
2012
Montreal
2012
Dissolution of Inclusions into Molten Slags
Al
M1 M3M24M23M22M21
CP
Ca
Mg
Si
Park, Jung and Lee: ISIJ Inter. No. 11, 2006
Ferrous Processing 121
Phase diagram between slag and inclusion to understand the
inclusion dissolution mechanism
2011 Montreal Montreal
2012
Montreal
2012
Dissolution of Inclusions into Molten Slags
10
20
30
40
50
60
70
80
90
102030405060708090
10
20
30
40
50
60
70
80
90
(CaO)0.525(SiO2)0.475
Al2O3 MgOweight percent
M24L+MgO
L+MgAl2O4+MgO
L+MgAl2O4
MgAl2O4
M23
M22
M21
M22M21M1
M3M24M23
Fig.8
M23
Park, Jung and Lee: ISIJ Inter. No. 11, 2006
Ferrous Processing 122
2011 Montreal Montreal
2012
Montreal
2012
Dissolution of Inclusions into Molten Slags
M22M21M1
M3M24M23
Fig.8
M3
10
20
30
40
50
60
70
80
90
102030405060708090
10
20
30
40
50
60
70
80
90
(CaO)0.58(SiO2)0.42
Al2O3 MgOweight percent
L + MgO + MgAl2O4
L + MgAl2O4
L + Ca2SiO4
L + MgO
MgAl2O4
M3
Park, Jung and Lee: ISIJ Inter. No. 11, 2006
Ferrous Processing 123
2011 Montreal Montreal
2012
Montreal
2012 Ferrous Processing 124
Application: Non-metallic Inclusions
Inclusion formation / composition in molten steels: Mn/Si/Ti steel
Inclusion stability diagram (phase diagram): Al/Ti steel
2011 Montreal Montreal
2012
- Evolution of non-metallic inclusions: Formation of acicular ferrite -
• Non-metallic inclusions: nucleation sites for acicular ferrite
• Acicular ferrite: enhances the strength of steel
Applications to Oxide metallurgy (Inclusion control)
Ferrous Processing 125
2011 Montreal Montreal
2012
Evolution of Non-metallic Inclusions
Morphologies of typical inclusions found in Fe-C-Mn-Si-O-S-Ti-Mg-Al-N
Mn/Si
Mn/Si
+Ti
Mn/Si
/Ti
+Mg
Mn/Si
/Ti/Mg
+AlMnS
Mg-Ti-Al-O
MgO
1㎛
Mg-Ti-(Al)-OMnS
MgO
1㎛
MnS
Mg-Al-(Ti)-O
MgO2㎛
MgO
MgAl2O4
Mn
S
1㎛
MgAl2O4MnS
1㎛
Ti-Mg-Mn-O
MnS 2㎛
MnSMg-Ti-Mn-O
1㎛ 1㎛
Mg-Ti-Mn-O
MnS
MgO
MgO
MnS
MgO
1㎛
2㎛
Mn-Si-O
MnS
2㎛
Mn-Ti-O
Mn-Si-O
MnS2㎛
Mn-Ti-O
Mn-Si-O
MnS 1㎛
Ti-Mn-O
MnS1㎛
Ti-O
MnS
(a)
(f) (h) (i)
(j) (k) (l) (m) (n)
Concentration of additional alloying element
(d)(b) (c) (e)
(g)
Mn/Si
Mn/Si
+Ti
Mn/Si
/Ti
+Mg
Mn/Si
/Ti/Mg
+AlMnS
Mg-Ti-Al-O
MgO
1㎛
Mg-Ti-(Al)-OMnS
MgO
1㎛
MnS
Mg-Al-(Ti)-O
MgO2㎛
MnS
Mg-Al-(Ti)-O
MgO2㎛
MgO
MgAl2O4
Mn
S
1㎛
MgAl2O4MnS
1㎛
Ti-Mg-Mn-O
MnS 2㎛
Ti-Mg-Mn-O
MnS 2㎛
MnSMg-Ti-Mn-O
1㎛
MnSMg-Ti-Mn-O
1㎛ 1㎛
Mg-Ti-Mn-O
MnS
MgO
1㎛
Mg-Ti-Mn-O
MnS
MgO
MgO
MnS
MgO
1㎛
MgO
MnS
MgO
1㎛
2㎛
Mn-Si-O
MnS
2㎛
Mn-Si-O
MnS
2㎛
Mn-Ti-O
Mn-Si-O
MnS2㎛
Mn-Ti-O
Mn-Si-O
MnS 1㎛
Ti-Mn-O
MnS1㎛
Ti-O
MnS
(a)
(f) (h) (i)
(j) (k) (l) (m) (n)
Concentration of additional alloying element
(d)(b) (c) (e)
(g)
Fe-0.1C-0.0035S-1.45Mn-0.1Si
-0.015Ti-0.0025O-0.03N+Mg
Ferrous Processing 126
2011 Montreal Montreal
2012
Evolution of Non-metallic Inclusions
(PB) (IL)
(MgO/Sp) (Sp)
(MgO)
Mg=2ppm 4
16
52
35
Thermodynamic Calculations
• Accurate prediction of inclusions phases
• Application to high strength steel design
Ferrous Processing 127
2011 Montreal Montreal
2012
Montreal
2012
Inclusion evolution with temperature: Mn/Si/Ti steel
MS-c
SLAGA#1
SLAGA#1
SLAGA#1
ILMEA#1
ILMEA#1
Rhod
OlivA
PSEU
98.2769 Fe + 0.1 C + 1.5 Mn + 0.1 Si +
c:\Workshop\Equi0.res 3May11
T(C)
wt
pp
m
1000 1100 1200 1300 1400 1500 1600
0
100
200
300
400
500
600
Select all phases (pure solids and
solutions) with amount > 0
FToxid : oxide inclusions
FTmisc: FeLq, MnS solid (MS_c)
FSStel: solid steel phases (fcc, bcc)
Ferrous Processing 128
2011 Montreal Montreal
2012
Montreal
2012
Wire
Inclusion (ex., alumina)
Crack Initiation
• Undeformable Inclusion should be removed
• Liquid phase is desirable at process
temperature (~1200oC)
Application to Tire-Cord Steel (Mn/Si deoxidation)
Tire-Cord Steel
Thin Sheet
Inclusion (ex., alumina)
Crack Initiation
Surface Quality Fe-36%Ni Invar Steel
0.15~0.38mm diameter
150µm thickness
Mn/Si Deoxidation
Ferrous Processing 129
2011 Montreal Montreal
2012
Montreal
2012
MnO-Al2O3-SiO2 Phase Diagram
Target Inclusion
Composition
MnO Al2O
3Weight %
1890
1194
1249
1239
1527
1595
1180
1156
1135
1119
1465
1143
1166
1328
1251
1293
1465
Mn2SiO4
MnSiO3
MnAl2O4
Al6Si2O13
Mn2Al4Si5O18
Mn3Al2Si3O12
Corundum
1800
1700
1600
1500
1400
1300
2000
1900
18001
70016001500
1400
1300
1200
1400
1300
Galaxite
Manganosite
2 Liquids
Mullite
Rhodonite
Tephroite
1769
1702
1702
(1723)
(2054)(1842)
1600
Tridymite
Spessarti
te
(1890)(1347)
MnO/SiO2 = 0.5
MnO/SiO2 = 1.0
MnO/SiO2 = 2.0
1150
SiO2
Low liquidus
temperature region
(1100oC ~ 1200
oC)
Cristobalit
e
Cristobalite: SiO2
Tridymite: SiO2
Rhodonite: MnSiO3
Spessartite: Mn3Al2Si3O12
Tephroite: Mn2SiO4
Manganosite: MnOGalaxite: MnAl2O4
Corundum: Al2O3
Mullite: Al6Si2O13
MnO Al2O
3Weight %
1890
1194
1249
1239
1527
1595
1180
1156
1135
1119
1465
1143
1166
1328
1251
1293
1465
Mn2SiO4
MnSiO3
MnAl2O4
Al6Si2O13
Mn2Al4Si5O18
Mn3Al2Si3O12
Corundum
1800
1700
1600
1500
1400
1300
2000
1900
18001
70016001500
1400
1300
1200
1400
1300
Galaxite
Manganosite
2 Liquids
Mullite
Rhodonite
Tephroite
1769
1702
1702
(1723)
(2054)(1842)
1600
Tridymite
Spessarti
te
(1890)(1347)
MnO/SiO2 = 0.5
MnO/SiO2 = 1.0
MnO/SiO2 = 2.0
1150
SiO2
Low liquidus
temperature region
(1100oC ~ 1200
oC)
Cristobalit
e
Cristobalite: SiO2
Tridymite: SiO2
Rhodonite: MnSiO3
Spessartite: Mn3Al2Si3O12
Tephroite: Mn2SiO4
Manganosite: MnOGalaxite: MnAl2O4
Corundum: Al2O3
Mullite: Al6Si2O13
Jung et al., Metall. Mater. Trans. B, 2004, vol. 35B, pp. 259-268
Ferrous Processing 130
2011 Montreal Montreal
2012
Montreal
2012
Inclusion composition with steel composition
Jung et al., Metall. Mater. Trans. B, 2004, vol. 35B, pp. 259-268
Kang and Lee, ISIJ Inter., 2004.
10
20
30
40
50
60
70
80
90
102030405060708090
10
20
30
40
50
60
70
80
90
SiO2
MnO Al2O3Weight %
wt%Mn / wt%Si = 9
10
52
1
0.5
0.2
0.1
wt%Mn / wt%Si = 1
wt%Mn / wt%Si = 0.1
T =1550oC
Liquid Oxide
L + MnO L + MnAl2O4
L + Al2O3
L + Mullite
L + SiO2
MnO/SiO2 = 1.0
Mn + Si = 1wt%
Ferrous Processing 131
2011 Montreal Montreal
2012
Montreal
2012
Inclusion calculation in Mn/Si deoxidation
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.10.20.30.40.50.60.70.80.9
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
SiO2
MnO Al2O3mass fraction
ASlag-liq + AMonoxide ASlag-liq + MnAl2O4(s)
ASlag-liq + M2O3(corundum)
ASlag-liq + Mullite
ASlag-liq + SiO2(s6)
MnO - Al2O3 - SiO2
1600oC
Ferrous Processing 132
2011 Montreal Montreal
2012
Montreal
2012
Inclusion calculation in Mn/Si deoxidation
Calculation of the inclusion trajectory using Equilib
The compositions of Mn and Si are set based on the target Mn/Si ratio and Mn+Si content
Oxygen content should be controlled reasonably. If O is too high, Mn and Si will be largely
changed from original target composition after rxn with oxygen.
Ferrous Processing 133
2011 Montreal Montreal
2012
Montreal
2012
Inclusion calculation in Mn/Si deoxidation
Mn + Si + Al + O (Mn,Si,Al) oxide inclusion
After deoxidation, Mn ~ 0.5 and Si ~ 0.5
(Target steel composition: Mn/Si = 1 and Mn+Si = 1)
Extraction of slag composition
Ferrous Processing 134
2011 Montreal Montreal
2012
Montreal
2012
Inclusion calculation in Mn/Si deoxidation
Slag #1
(stable slag) Slag #2
(metastable or same as #1
except in case of stable miscibility gap)
Composition from Slag #1
A corner = wt%SiO2/100
B corner = (wt%MnO+Mn2O3+FeO+Fe2O3)/100
C corner = wt%Al2O3/100
Ferrous Processing 135
2011 Montreal Montreal
2012
Montreal
2012
Inclusion calculation in Mn/Si deoxidation
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.10.20.30.40.50.60.70.80.9
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
SiO2
MnO Al2O3mass fraction
ASlag-liq + AMonoxide ASlag-liq + MnAl2O4(s)
ASlag-liq + M2O3(corundum)
ASlag-liq + Mullite
ASlag-liq + SiO2(s6)
MnO - Al2O3 - SiO2
1600oC
10
20
30
40
50
60
70
80
90
102030405060708090
10
20
30
40
50
60
70
80
90
SiO2
Al2O3
Mn/Si = 10
5.0
2.01.0
0.5
Fe Liquid
[%Mn] + [%Si] = ~1.0
T = 1600oC
1.0
Kang and Lee [35]
SiO2
Al2O3
1200oC
liquidus
SiO2
MnO(+FeO) Al2O3
0.2
0.1
0.35
0.52
1.1
0.50
11.1
9.9
Ohta and Suito[34]
weight percent
Slag composition is slightly off
from phase diagram because the
actual slag is containing FetO
and Mn2O3 as well.
According to calculations,
mullite and Al2O3 are
forming subsequently
after slag
Ferrous Processing 136
2011 Montreal Montreal
2012
Montreal
2012
Inclusion calculation in Mn/Si deoxidation
Al2O3(SLAGA#1)
SiO2(SLAGA#1)
FeO(SLAGA#1)
Fe2O3(SLAGA#1)
MnO(SLAGA#1)
98.995 Fe + 0.5 Mn + 0.5 Si + <A> Al +
c:\Workshop\Equi0.res 3May11
weight % Al_FeLQ
we
igh
t %
0 0.0002 0.0004 0.0006 0.0008 0.001
0
10.00
20.00
30.00
40.00
50.00
60.00
70.00
80.00
90.00
100.00
Soluble Al vs. Inclusion composition
Ferrous Processing 137
2011 Montreal Montreal
2012
Nozzle Clogging in Ti-bearing Al-killed steel
• Kawashima et al., CAMP-ISIJ (1991)
– Liquid Al-Ti-O (reoxidization) attached to Al2O3 inclusions
• Basu et al. ISIJ Int. (2004)
Significant difference of nozzle clogging of Ti-bearing steel from and Ti-free
steel is the existence of the Al-Ti-O inclusions covering Al2O3 core oxides.
Reoxidation in tundish (high SiO2 slags) causes the nozzle clogging.
Ferrous Processing 138
2011 Montreal Montreal
2012
Inclusions generated by Reoxidation process
RH process after Ti addition (POSCO)
Doo et al. (2007)
Al2O3
Ti-Al-O hole
Reoxidation in Tundish
(high SiO2 slags)
Park et al. (2004)
Reoxidation in Tundish
Basu et al. (2004)
Ti/Al of outer layer = 1.0~1.5
Ferrous Processing 139
2011 Montreal Montreal
2012
Inclusion causing nozzle clogging in Al-killed Ti bearing steel
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.10.20.30.40.50.60.70.80.9
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
mole fraction
corundum
TiO2 + L
ilmenite + Ti3O5
Ti3O5 + L
co
run
du
m +
L
+ ilmenite + L
ilmenite + Llo
g P
O2 =
-11
-12
-13
-14
Al2O3
Ti2O3 TiO2
+ A
l2 T
iO5 +
LAl2TiO5 + L
Al2O3
Ti2O3 TiO2
Al2O3
Ti2O3 TiO2
Al2O3
Ti2O3 TiO2
Al2O3
Ti2O3 TiO2
Al2O3
Ti2O3 TiO2
Al2O3
Ti2O3 TiO2
T = 1600oC
-10
Liquid
Magneli + L
coru
ndum
-9.0
Ferrous Processing 140
2011 Montreal Montreal
2012
Calculated inclusion composition in Fe-Al-Ti-O liquid at 1600oC
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
0.10.20.30.40.50.60.70.80.9
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
Al2O3
Ti2O3TiO2 + FeOmole fraction
Al2O3
Ti2O3
Al2O3
Ti2O3
Al2O3
Ti2O3
Al2O3
Ti2O3
Al2O3
Ti2O3
Al2O3
Ti2O3
Al2O3
Ti2O3
Al2O3
Ti2O3
Al2O3
Ti2O3
corundum
L
ilmenite + Ti3O5 + LTi3O5 + L
corundum + L+ ilmenite + L
ilmenite + L
Ti =
10p
pm
50
100
500
1000
Similar to Mn/Si
deoxidation calculations
Ferrous Processing 141
2011 Montreal Montreal
2012
Newly calculated Inclusion diagram of Fe-Al-Ti-O system
Al2O3
Ti2O3
Ti3O5
56[wt ppm O]
20
15
12
10
50
30
20
15
12
80
30
810 =4.5 ppm
50T = 1600
oC
Liquid
log [wt% Al]
log
[w
t% T
i]
-4.0 -3.5 -3.0 -2.5 -2.0 -1.5 -1.0 -0.5
-3.0
-2.5
-2.0
-1.5
-1.0
-0.5
0.0
0.5
1.0
Existence of Liquid
Al2O3-Ti2O3-TiO2
phase at 1600oC
Al deoxidation + Ti addition
Reoxidation
(Nozzle Clogging)
Ferrous Processing 142
2011 Montreal Montreal
2012
Al killed Ti bearing steel
Ferrous Processing 143
2011 Montreal Montreal
2012
Al killed Ti bearing steel
Ferrous Processing 144
2011 Montreal Montreal
2012
Reoxidation of Al killed Ti bearing steel
Ferrous Processing 145
“Recycle all streams”
• you don’t have to save the stream one by one. But the results
will be used only one time because it is not saved under
special stream name.
• Convenient option when you want to do one calculation
2011 Montreal Montreal
2012
Reoxidation of Al killed Ti bearing steel
Ferrous Processing 146
Addition of oxygen to simulation
reoxidation phenomena.
Real source of oxygen could be
high SiO2 slag or refractories
2011 Montreal Montreal
2012
Reoxidation of Al killed Ti bearing steel
Ferrous Processing 147
SLAGA#1
SLAGA#1
SLAGA#1
CORU#1
CORU#1
CORU#1
CORU#1
100% [Rc_Fe-liq] + 100% [Rc_M2O3(Corundum)] + <A> O2
C:\Slag-Steel-Inclusions\Equi0.res 25Sep12
Alpha
gra
m
0.00 0.01 0.02 0.03 0.04 0.05
0.00
0.05
0.10
0.15
0.20
+ 0.12253 gram ASlag-liq#1
(0.12253 gram, 1.1558E-03 mol)
(1600 C, 1 atm, a=1.0000)
( 33.379 wt.% Al2O3 FToxid
+ 0.17724 wt.% SiO2 FToxid
+ 0.83830 wt.% FeO FToxid
+ 1.1051E-03 wt.% Fe2O3 FToxid
+ 1.9943 wt.% MnO FToxid
+ 40.135 wt.% Ti2O3 FToxid
+ 23.475 wt.% TiO2 FToxid
+ 1.0928E-03 wt.% Mn2O3 FToxid)
This calculation shows that mixed inclusion of Al2O3(s) and liquid (Al2O3-TiO2-Ti2O3)
can be formed by the reoxidation of Al-killed Ti bearing steel.
Nozzle clogging.
2011 Montreal Montreal
2012
TiN formation in Al killed and Ti bearing steel
Ferrous Processing 148
Original steel composition at 1600C: high N and high Ti may form TIN
2011 Montreal Montreal
2012
TiN formation in Al killed and Ti bearing steel
Ferrous Processing 149
TiN(s)
CORU#1CORU#1CORU#1CORU#1
100% [Rc_Fe-liq] + 100% [Rc_M2O3(Corundum)]
C:\Slag-Steel-Inclusions\Equi0.res 25Sep12
T(C)
gra
m
1500 1510 1520 1530 1540 1550 1560 1570 1580 1590 1600
0.00
0.05
0.10
TiN(s) CORU#1CORU#1CORU#1CORU#1
BC
C
FeL
Q
100% [Rc_Fe-liq] + 100% [Rc_M2O3(Corundum)]
C:\Slag-Steel-Inclusions\Equi0.res 25Sep12
T(C)
gra
m
1500 1510 1520 1530 1540 1550 1560 1570 1580 1590 1600
0
10
20
30
40
50
60
70
80
90
100
Liquid steel
+ BCC Liquid steel
During the solidification,
a large amount of TiN can be formed.
2011 Montreal Montreal
2012
Montreal
2012
Inclusion diagram: Fe-Al-O, Al deoxidation
(1): draw rectangular diagram
Ferrous Processing 150
2011 Montreal Montreal
2012
Montreal
2012
Inclusion diagram: Fe-Al-O, Al deoxidation
(2): change X- and Y-axis lower limit.
(3): change linear scale to log scale.
(3): change linear scale to log scale.
(2): change X- and Y-axis lower limit.
“After changing the axes to log
scale, move all curves to +2 in
linear scale“
Ferrous Processing 151
2011 Montreal Montreal
2012
Montreal
2012
Inclusion diagram: Fe-Al-O, Al deoxidation
Fe-liq + M2O3(Corundum)
Fe-liq
Fe - Al - O
1600oC
log [wt% Al]
log
[w
t% O
]
-4 -3.5 -3 -2.5 -2 -1.5 -1 -.5 0
-4
-3.5
-3
-2.5
-2
-1.5
-1(4) Editing of title of x- and y-axis
Ferrous Processing 152
2011 Montreal Montreal
2012
Montreal
2012
M2O3(corundum) + Fe-liq
Fe-liq
Fe - Al - O - Ti
1600oC, mass O/(Fe+Al+O+Ti) = 5E-6
wt% Al
wt%
Ti
-5 -4.5 -4 -3.5 -3 -2.5 -2 -1.5 -1 -0.5 0
-3
-2.7
-2.4
-2.1
-1.8
-1.5
-1.2
-0.9
-0.6
-0.3
0
log wt% Al
log w
t% T
i
Inclusion diagram: Fe-Al-Ti-O, Al/Ti deoxidation
Fe-liq + M2O3(Corundum)
Fe-liq
Fe - Al - O
1600oC
log [wt% Al]
log
[w
t% O
]
-4 -3.5 -3 -2.5 -2 -1.5 -1 -.5 0
-4
-3.5
-3
-2.5
-2
-1.5
-1
Ferrous Processing 153
2011 Montreal Montreal
2012
Montreal
2012
M2O3(corundum) + Fe-liq
Fe-liq
Fe-liq
Pseudobrookite + Fe-liq
Pseudobrookite + Fe-liq
BIlmenite + Fe-liq
Fe - Al - O - Ti
1600oC, mass O/(Fe+Al+O+Ti) = 10E-6
log wt% Al
log w
t% T
i
-5 -4.5 -4 -3.5 -3 -2.5 -2 -1.5 -1 -0.5 0
-3
-2.7
-2.4
-2.1
-1.8
-1.5
-1.2
-0.9
-0.6
-0.3
0
Al2O3
Ilmenite (Ti2O3-rich phase)
Ti3O5
56[wt ppm O]
201512
10
50
30
20
1512
80
30
810 =4.5 ppm
50T = 1600
oC
Liquid
log [wt% Al]
log
[w
t% T
i]
-4.0 -3.5 -3.0 -2.5 -2.0 -1.5 -1.0 -0.5-3.0
-2.5
-2.0
-1.5
-1.0
-0.5
0.0
0.5
1.0
M2O3(corundum) + Fe-liq
Fe-liq
Fe - Al - O - Ti
1600oC, mass O/(Fe+Al+O+Ti) = 5E-6
wt% Al
wt%
Ti
-5 -4.5 -4 -3.5 -3 -2.5 -2 -1.5 -1 -0.5 0
-3
-2.7
-2.4
-2.1
-1.8
-1.5
-1.2
-0.9
-0.6
-0.3
0
log wt% Al
log w
t% T
i Inclusion diagram: Fe-Al-Ti-O, Al/Ti deoxidation
1) Change oxygen content and calculate similar diagram
2) Superimpose all the diagram together
3) Calculate the phase boundaries from Equilib (or simply
connect boundaries in the calculated diagram)
Iso oxygen 5ppm line
Ferrous Processing 154
2011 Montreal Montreal
2012
Montreal
2012
Inclusion after Mn/Si deoxidation
Ferrous Processing 155
2011 Montreal Montreal
2012
Montreal
2012 Ferrous Processing 156
Application: Solidification of slag and steel
Scheil Cooling calculations
2011 Montreal Montreal
2012
T1
T2
T3
Te
T1
T2
T3
T<Te
L1
L2 L3
L2
L3
L1
Scheil
Cooling
Equilib.
Cooling
Equilibrium cooling and Scheil cooling
Scheil Cooling
Solidification microstructure
Ferrous Processing 157
2011 Montreal Montreal
2012
Montreal
2012
Equilibrium cooling of the CaO-SiO2-Al2O3-MgO slag
Equilibrium solidification of slag
Ferrous Processing 158
2011 Montreal Montreal
2012
Montreal
2012
Equilibrium solidification of slag: plot amount vs. temperature
2
1
3
4
5
Ferrous Processing 159
2011 Montreal Montreal
2012
Montreal
2012
Ca3MgSi2O8(s) Ca3MgSi2O8(s) Ca3MgSi2O8(s)
SLAGA#1
SPINA#1 SPINA#1 SPINA#1
SPINA#1
Mel_ Mel_ Mel_
40 CaO + 10 MgO + 20 Al2O3 + 30 SiO2
c:\FactSage\casestudy\Equi0.res 21May09
T(C)
gra
m
1000 1100 1200 1300 1400 1500 1600
0
020
040
060
080
100
Equilibrium solidification of slag: plot amount vs. temperature
Equilibrium solidification is completed at ~ 1410oC
Ferrous Processing 160
2011 Montreal Montreal
2012
Montreal
2012
Scheil cooling solidification of slag
Scheil cooling of the CaO-SiO2-Al2O3-MgO slag
Scheil cooling temperature setup:
(initial_T final_T)
Ferrous Processing 161
2011 Montreal Montreal
2012
Montreal
2012
Ca3MgSi2O8(s)Ca3MgSi2O8(s)
SLAGA#1SLAGA#1
SLAGA#1
SLAGA#1SPINA#1
SPINA#1SPINA#1
Mel_
Mel_
OlivA#1
40 CaO + 10 MgO + 20 Al2O3 + 30 SiO2
c:\FactSage\casestudy\Equi0.res 22May09
T(C)
gra
m
1225 1275 1325 1375 1425 1475 1525 1575
0
020
040
060
080
100
Equilibrium solidification of slag: plot amount vs. temperature
Scheil cooling solidification is completed at ~ 1320oC
Ferrous Processing 162
2011 Montreal Montreal
2012
Montreal
2012
Solidification of mould flux
Ferrous Processing 163
Using ‘CON1’ database
2011 Montreal Montreal
2012
Equilibrium cooling of Fe-20Mn-1C-1Al TWIP steel
Equilibrium solidification of steel: TWIP steel
Ferrous Processing 164
2011 Montreal Montreal
2012
CEME
CEME
FCC
FCCFCC FCC
FCC
FE-L
78 Fe + 20 Mn + C + Al
T(C)
gra
m
600 700 800 900 1000 1100 1200 1300 1400
0
10
20
30
40
50
60
70
80
90
100
110
Equilibrium solidification of steel: TWIP steel
Ferrous Processing 165
2011 Montreal Montreal
2012
Scheil cooling solidification of steel: TWIP steel
Scheil cooling of Fe-20Mn-1C-1Al TWIP steel
Ferrous Processing 166
2011 Montreal Montreal
2012
FCC
FCC
FCC
FCC
FCC
FE-L
FE-L
FE-L
FE-L
FE-L
78 Fe + 20 Mn + C + Al
T(C)
gra
m
600 700 800 900 1000 1100 1200 1300 1400
0
10
20
30
40
50
60
70
80
90
100
110
Scheil solidification of steel: TWIP steel
Solidification is completed at ~ 1075oC which is
almost 100oC lower than equilibrium calculation.
Ferrous Processing 167
2011 Montreal Montreal
2012
Montreal
2012 Ferrous Processing 168
Application: Refractory design
Chemical stability
Thermal stability
2011 Montreal Montreal
2012
Montreal
2012
Simple counter-cross inter-diffusion calculation: <A> option
Counter-cross inter-diffusion reactions at interface can be simulated with the
<A> option in Equilib. This assumes the diffusivities of all components in both
materials are the same.
Materials #1 Materials #2
Materials #2 Materials #1
concentr
ation
<A> reactants #1 + <1-A> reactants #2
Ferrous Processing 169
2011 Montreal Montreal
2012
Montreal
2012 Ferrous Processing 170
Counter-cross reaction: refractory / slag
Slag
60%CaO-40%SiO2
Refractory
95%Al2O3-5%MgO
2011 Montreal Montreal
2012
Montreal
2012 Ferrous Processing 171
Counter-cross reaction: refractory / slag
Al2O3(s4) CaMg2Al16O27(s)
Ca2Mg2Al28O46(s)
Ca2Mg2Al28O46(s)
SLAGA#1
SLAGA#1
SLAGA#1 SLAGA#1
<0.6A> CaO + <0.4A> SiO2 + <0.95-0.95A> Al2O3 + <0.05-0.05A> MgO
c:\Workshop\AlloyDesign\Equi0.res 9May10
Alpha
gra
m
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
0.0
0.2
0.4
0.6
0.8
1.0
2011 Montreal Montreal
2012
Montreal
2012
[Sla
g]
[Refr
acto
ry]
Al2O3
FeO
MgO
Cr2O3
(1-x) refractory + x slag (by weight)
com
po
siti
on
of
spin
el,
wt%
-0.1 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1
0
10
20
30
40
50
60
70
80
90
100
[Refractory]
[Slag]
Spinel
Periclase
[Sla
g]
[Refr
acto
ry] Slag
Periclase
Spinel
(1-x) refractory + x slag (by weight)
rela
tiv
e a
mo
un
t o
f ea
ch p
ha
se,
wt%
-0.1 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1
0
10
20
30
40
50
60
70
80
90
100
Al2O3
FeO
MgO
Cr2O3
[Sla
g]
[Refr
acto
ry]
(1-x) refractory + x slag (by weight)
com
po
siti
on
of
per
icla
se,
wt%
-0.1 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1
0
10
20
30
40
50
60
70
80
90
100
[Sla
g]
[Refr
acto
ry]
CaO
SiO2
Al2O3
MgO
FeOCr2O3
(1-x) refractory + x slag (by weight)
com
po
siti
on
of
sla
g,
wt%
-0.1 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1
0
10
20
30
40
50
60
70
slag
spinel
periclase
refractories; 58MgO-6.5Al2O3-21 Cr2O3-13.5FeO
slag; 50CaO-40SiO2-10Al2O3 (in wt%)
Counter-cross reaction: Refractories in VOD
T=1650oC
Jung et al., Taikabutsu, vol. 56, 2004, pp. 382-386.
Ferrous Processing 172
2011 Montreal Montreal
2012
RH Vessel Refractory
Snorkel
RH Vessel
Ladle
O2 Lance
RH OB
• High amount of oxygen blowing
• Increase of Ferro-alloy (Al, Si, Mn, etc) addition
→ More severe local corrosion of RH vessel refractory
Normal corrosion
Abnormally severe corrosion
Flow pattern in RH
CFD model
Ferrous Processing 173
2011 Montreal Montreal
2012
Quite enough thermodynamic database
(gas, molten steel, slag, refractory, etc…)
Write kinetic process using Macro :
input/output to Excel spread sheet
Reaction zone 1
Reaction zone 2
Reaction zone 3
Heat & Mass balance !!
…… Van Ende et al: ‘A Kinetic Model for the Ruhrstahl Heraeus (RH)
Degassing Process’, Metall. Mater. Trans. B, 2011, p. 477
Concept for RH process simulation modeling
Ferrous Processing 174
2011 Montreal Montreal
2012
RH Vessel Refractory
Ferrous Processing 175
Predicted slag composition in RH
vessel from RH process simulation
M.-K. Cho, M.-A. Van Ende, T.-H. Eun and I.-H. Jung, “Investigation of slag-refractory interactions for the
Ruhrstahl Heraeus (RH) vacuum degassing process in steelmaking”, J. Eur. Ceram. Soc., 2012, 32,1503-1517.
Experimental and calculation conditions
F1,F2 C1,C2
2011 Montreal Montreal
2012
Refractory Finger tests at 1600oC
Ferrous Processing 176
2011 Montreal Montreal
2012
Thermodynamic Calculations: Refractories – Slag Interactions
Ferrous Processing 177
2011 Montreal Montreal
2012
Ladle Glaze formation
Dipping time: 120 sec CaO SiO2 Al2O3 MgO
54.06 10.47 26.24 9.23
Slag composition (wt.%)
CaO SiO2 Al2O3 MgO
2.35 0.76 88.06 8.35
Refractory composition (wt.%)
As-received Dipped for 120 sec Ferrous Processing 178
2011 Montreal Montreal
2012
Glazed Refractory
Glaze
Ferrous Processing 179
2011 Montreal Montreal
2012
Montreal
2012
Glaze (Reaction product of slag and refractory)
Slag
Spinel
CaAl12O19
CaAl4O7
Al2
O3
x slag + (1-x) refractory
ph
ase
dis
trib
uti
on
(w
t%)
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
0
10
20
30
40
50
60
70
80
90
100
Al2O3
CaO
SiO2
MgO
x slag + (1-x) refractory
sla
g c
om
po
siti
on
(w
t %
)
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
0
10
20
30
40
50
60
70
spinel islands
Glaze composition (glass)
CaO SiO2 Al2O3 MgO
35.8 6.6 51.1 6.5
Glaze area: glass + spinel
Original refractory Ladle slag
Ferrous Processing 180
2011 Montreal Montreal
2012
Montreal
2012
Equilibrium stability of 20MgO-78Al2O3-2CaO refractories
Equilibrium stability calculations with temperature: refractories
Ferrous Processing 181
2011 Montreal Montreal
2012
Montreal
2012
CaAl4O7(s)
CaAl4O7(s)
CaMg2Al16O27(s) CaMg2Al16O27(s) CaMg2Al16O27(s)
CaMg2Al16O27(s)
SPINA SPINA SPINA
SPINA
SLAGA#1SLAGA#1
2 CaO + <A> MgO + <98-A> Al2O3
c:\FactSage\casestudy\Equi0.res 22May09
T(C)
gra
m
1200 1300 1400 1500 1600 1700 1800
0
10
20
30
40
50
60
70
80
90
Equilibrium stability calculations with temperature: refractories
The refractory is mechanically unstable above 1600oC:
- considerable volume change due to the significant change in phase distribution
The refractory cannot be used above 1690oC:
- significant amount of liquid phase formation
Ferrous Processing 182
2011 Montreal Montreal
2012
Montreal
2012
Thermal Stability test of Refractories
wt% REF-1 2 3 4 5 6
Al2O3 88 60 11 4 0.5 0.5
MgO 9 38 58 61 89 75
CaO 2 2 0.9 0.7
Cr2O3 20 29
Fe2O3 8.8 4.8
SiO2 1.6 0.4 0.5 1.2
C 7 17
Al 2 4
MgO
Spinel
SlagCa3MgAl4O10
(gram) 60 Al2O3 + 38 MgO + 2 CaO
Temperature (C)
ph
ase
dis
trib
uti
on
(w
t%)
1200 1300 1400 1500 1600 1700 1800 1900
0
10
20
30
40
50
60
70
80
90
Spinel
CaMg2Al16O27
Al2O3
Ca2Mg2Al28O46
CaAl12O19
(gram) 88 Al2O3 + 9 MgO + 2 CaO
Temperature (C)
ph
ase
dis
trib
uti
on
(w
t%)
1200 1300 1400 1500 1600 1700 1800 1900
0
10
20
30
40
50
60
70
80
90
REF-1 REF-2
Ferrous Processing 183
2011 Montreal Montreal
2012
Thermal Stability test of Refractories
CaMgSiO4
Mg2SiO4
Slag
Spinel
MgO
(gram) 11 Al2O3 + 58 MgO + 0.9 CaO + 20 Cr2O3 + 8.8 Fe2O3 + 1.6 SiO2
Temperature (C)
ph
ase
dis
trib
uti
on
(w
t%)
1200 1300 1400 1500 1600 1700 1800 1900
0
10
20
30
40
50
60
70
80
90
Slag
Spinel
MgO
a-Ca2SiO4a'Ca2SiO4
(gram) 4 Al2O3 + 61 MgO + 0.7 CaO + 29 Cr2O3 + 4.8 Fe2O3 + 0.4 SiO2
Temperature (C)
ph
ase
dis
trib
uti
on
(w
t%)
1200 1300 1400 1500 1600 1700 1800 1900
0
10
20
30
40
50
60
70
80
90
C
MgO
Al4C3Spinel
(gram) 0.5 Al2O3 + 89 MgO + 0.5 SiO2 + 7 C + 2 Al
Temperature (C)
ph
ase
dis
trib
uti
on
(w
t%)
1200 1300 1400 1500 1600 1700 1800 1900
0
10
20
30
40
50
60
70
80
90
REF-5
REF-3 REF-4
Depending on the refractory compositions,
the refractory components can vary drastically.
Formation of liquid
Stability of refractory
Change in MgO/Spinel fraction
Mechanical wear resistance
Volume change
Ferrous Processing 184
2011 Montreal Montreal
2012
Refractory – Liquid Inclusion Interactions
Ferrous Processing 185
Stopper Head
SEN Collar
Inner side/mouth
of SEN
Stopper (Al2O3-C)
Corroded area
Inner side of SEN
SEN (submerged entry nozzle)
melt
M.-K. Cho and I.-H. Jung, “Corrosion of nozzle refractories by liquid inclusion in high oxygen steels”,
ISIJ Inter. 2012, vol. 52, pp. 1289-1296.
2011 Montreal Montreal
2012
Refractory – Liquid Inclusion Interactions
Ferrous Processing 186
Ple
ase s
ee t
he d
eta
ils in t
he I
SIJ
paper
2011 Montreal Montreal
2012
Refractory – Liquid Inclusion Interactions
Ferrous Processing 187
Please see the details in the ISIJ paper
2011 Montreal Montreal
2012
Refractory – Liquid Inclusion Interactions
Ferrous Processing 188
Ple
ase s
ee t
he d
eta
ils in t
he I
SIJ
paper
Relative Stability of the refractories against liquid MnO-SiO2 type inclusion
2011 Montreal Montreal
2012
Refractory-Steel Interaction
Ferrous Processing 189
2011 Montreal Montreal
2012
Refractory-Steel Interaction
Ferrous Processing 190
FeLQ FeLQ FeLQ FeLQ
SPINA#1
SPINA#1
SPINA#1
SPINA#1
MeO_A
MeO_A
MeO_A
CO
RU
#1
95 Fe + 4 Mn + Si + <100-100A> MgO +
C:\Slag-Steel-Inclusions\Equi0.res 24Sep12
Alpha
gra
m
0.0 0.2 0.4 0.6 0.8 1.0
0
20
40
60
80
100
Mn_FeLQ Mn_FeLQ Mn_FeLQ Mn_FeLQ
Si_FeLQ Si_FeLQ Si_FeLQ Si_FeLQ
Al_FeLQAl_FeLQ Al_FeLQ Al_FeLQMg_FeLQ Mg_FeLQ Mg_FeLQ Mg_FeLQO_FeLQ O_FeLQ O_FeLQ O_FeLQ
95 Fe + 4 Mn + Si + <100-100A> MgO +
C:\Slag-Steel-Inclusions\Equi0.res 24Sep12
Alpha
we
igh
t %
0.0 0.2 0.4 0.6 0.8 1.0
0.0
1.0
2.0
3.0
4.0
5.0
6.0
Change in steel composition
Change in the amount of phases
<A> Al2O3 + <1-A> Al2O3
<A> Al2O3 + <1-A> Al2O3
2011 Montreal Montreal
2012
85%Mn-15%Fe melt
Refractories
1g Mn-Fe melt + 1g refractory (MgO-Cr2O3)
Melt / refractory reactions simulation
Liquid
Spinel (MgCr2O4-MnCr2O4)
(MgO-MnO)
0.15 Fe + 0.85 Mn + <A> MgO + <1-A> Cr2O3
<A> MgO + <1-A> Cr2O3
gra
m
0.0 0.2 0.4 0.6 0.8 1.0
0
0.2
0.4
0.6
0.8
1
1.2
MgO
MnO
Cr2O3
0.15 Fe + 0.85 Mn + <A> MgO + <1-A> Cr2O3
<A>MgO + <1-A>Cr2O3
we
igh
t %
0.0 0.2 0.4 0.6 0.8 1.0
0
10
20
30
40
50
60
70
80
90
100
Cr2O3 MgCr2O4 MgO
(Spinel)
(MgO-MnO)
MgCr2O4
MnCr2O4
0.15 Fe + 0.85 Mn + <A> MgO + <1-A> Cr2O3
<A> MgO + <1-A> Cr2O3
we
igh
t %
0.0 0.2 0.4 0.6 0.8 1.0
0
10
20
30
40
50
60
70
80
90
100
Fe
MnCr
0.15 Fe + 0.85 Mn + <A> MgO + <1-A> Cr2O3
<A> MgO + <1-A> Cr2O3
we
igh
t %
0.0 0.2 0.4 0.6 0.8 1.0
0
10
20
30
40
50
60
70
80
90
100
Steel
High Mn-Fe melt storage for TWIP Steel production
Ferrous Processing 191
2011 Montreal Montreal
2012
LIQU
(MgO-MnO)
Corun
dum
(Al2
O3)
Spinel (MgAl2O
4-MnAl2O
4)
0.15 Fe + 0.85 Mn + <A> MgO + <1-A> Al2O3
<A> MgO + <1-A> Al2O3
gra
m
0.0 0.2 0.4 0.6 0.8 1.0
0
0.2
0.4
0.6
0.8
1
MgO
MnO
0.15 Fe + 0.85 Mn + <A> MgO + <1-A> Al2O3
<A> MgO + <1-A> Al2O3
we
igh
t %
0.0 0.2 0.4 0.6 0.8 1.0
0
10
20
30
40
50
60
70
80
90
100
Fe
Mn
Al
0.15 Fe + 0.85 Mn + <A> MgO + <1-A> Al2O3
<A> MgO + <1-A> Al2O3
we
igh
t %
0.0 0.2 0.4 0.6 0.8 1.0
0
10
20
30
40
50
60
70
80
90
100
MgAl2O4
MnAl2O4
Al8O12
0.15 Fe + 0.85 Mn + <A> MgO + <1-A> Al2O3
<A> MgO + <1-A> Al2O3
we
igh
t %
0.0 0.2 0.4 0.6 0.8 1.0
0
10
20
30
40
50
60
70
80
90
100
Al2O3 MgAl2O4 MgO
MgO
Spinel Steel
1g Mn-Fe melt + 1g refractory (MgO-Al2O3)
High Mn-Fe melt storage for TWIP Steel production
Ferrous Processing 192
2011 Montreal Montreal
2012
Fe
Mn
Al
<77.9B> Fe + <20B> Mn + <1.5B> Al + <0.6B> C +
<A> MgO + <1-A> Al2O3
we
igh
t %
0.0 0.2 0.4 0.6 0.8 1.0
0
10
20
30
40
50
60
70
80
90
100
Liquid
MgO
Al2 O
3
MgAl2 O
4 -MnAl2 O
4
<77.9B> Fe + <20B> Mn + <1.5B> Al + <0.6B> C +
<A> MgO + <1-A> Al2O3g
ram
0.0 0.2 0.4 0.6 0.8 1.0
0
0.2
0.4
0.6
0.8
1
Twip steel
Refractories
Refractory for TWIP steel: Fe-20%Mn-1.5%Al-0.6%C
T = 1500oC
Steel
MgO-Al2O3 type: Very stable refractory
Ferrous Processing 193
2011 Montreal Montreal
2012
Twip steel
Refractories
Refractory for TWIP steel: Fe-20%Mn-1.5%Al-0.6%C
T = 1500oC
Steel
MgO-Cr2O3 type: less stable
Cr pickup
Al loss
Fe
Mn
Cr
<77.9B> Fe + <20B> Mn + <1.5B> Al + <0.6B> C +
<A> MgO + <1-A> Cr2O3
we
igh
t %
0.0 0.2 0.4 0.6 0.8 1.0
0
10
20
30
40
50
60
70
80
90
100
Steel
MgC
r2 O
4 -MnC
r2 O
4M
gO-M
nO-s
mall C
r 2O 3
MgAl2O4-MnAl2O4
Cr
2 O3 -A
l2 O3
<77.9B> Fe + <20B> Mn + <1.5B> Al + <0.6B> C +
<A> MgO + <1-A> Cr2O3
gra
m
0.0 0.2 0.4 0.6 0.8 1.0
0
0.2
0.4
0.6
0.8
1
Ferrous Processing 194
2011 Montreal Montreal
2012
Enthalpy of slags
• When slag forms from pure oxides, a certain
amount of heat (enthalpy) is needed.
• When slag is cooled down, a certain amount of
heat should be extracted.
• FactSage Phase diagram: Enthalpy diagram
Ferrous Processing 195
2011 Montreal Montreal
2012
Heat required to form and increase temperature of slag
Ferrous Processing 196
Pure FeO(s) is not in FToxid compound database
(Strictly speaking, FeO is non-stoichiometric
compound so it is in MeO solution)
Initial condition
FactSage can used two variables, <A> and <B>
<A> can be really varied and <B> should be constant
H = Hfinal – Hinitial
So initial conditions(phase,T,P) should be defined
2011 Montreal Montreal
2012 Ferrous Processing 197
Final condition
H = Hfinal – Hinitial
This is the heat we add to increase the
temperature up to 1600oC.
That is, H = Hslag at 1600C – Hinitial oxides at 25C
This is the enthalpy of the final
products at 1600oC
Heat required to form slag and increase the temperature of slag
2011 Montreal Montreal
2012
Heat required to form slag and increase the temperature of slag
Ferrous Processing 198
<A> MgO + <1-A-B> FeO + <B> SiO2
Alpha
De
lta
H(J
)
0.0 0.1 0.2 0.3 0.4 0.5
1475
1525
1575
1625
1675
1725
1775
1825
1875
1925
Fe(s) Fe(s) Fe(s) Fe(s)
SLAGA#1 SLAGA#1
SLAGA#1
SLAGA#1
MeO_A
OlivA
OlivA
<A> MgO + <1-A-B> FeO + <B> SiO2
C:\Slag-Steel-Inclusions\Equi0.res 23Sep12
Alpha
gra
m
0.0 0.1 0.2 0.3 0.4 0.5
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
slag
Sla
g+
Oliv
ine
Sla
g+
Oliv
ine+
MeO
Oliv
ine+
MeO
2011 Montreal Montreal
2012 Ferrous Processing 199
Enthalpy diagram: phase change with H
2011 Montreal Montreal
2012 Ferrous Processing 200
• Only X-Y type diagram allowed.
• Y axis should be Enthalpy (H-HTmin).
• Hinitial (HTmin) is the enthalpy of products stable at Tmin. For example, Fe2SiO4
(fayalite_olivine) and SiO2 are stable at 0% MgO and 30% SiO2 instead of FeO and
SiO2.
30%SiO2
Tinitial
Iso-Temperature
Enthalpy diagram option
Enthalpy diagram: phase change with H
2011 Montreal Montreal
2012
Enthalpy diagram: phase change with H
Ferrous Processing 201
If we increase the temperature of the mixture of (Monoxide + olivine) at 20 wt % MgO and 30 wt % SiO2
from 25 oC to 1625 oC, liquid slag is forming and the amount of heat required for this is about 2250 J/g.
125 oC
225 oC
325 oC
425 oC
525 oC
625 oC
725 oC
825 oC
925 oC
1025 oC
1125 oC
1225 oC
1325 oC
1425 oC
1525 oC
1625 oC
1725 oC
1825 oC
2025 oC2125
oC2225
oC2325
oC2425
oC
AMonoxide + AMonoxide#2 + AOlivine
AMonoxide + AOlivine
ASlag-liq + AMonoxide + AOlivine
ASlag-liq + AOlivine
ASlag-liq
ASlag-liq + AMonoxide
AOlivine + SiO2(s)
AOlivine + SiO2(s2)
AOlivine + SiO2(s4)
MgO - FeO - SiO2
SiO2/(MgO+FeO+SiO
2) (g/g) = 0.3, 1 atm
MgO/(MgO+FeO+SiO2) (g/g)
H -
H25 C
(J/g
)
0 0.1 0.2 0.3 0.4 0.5 0.6
0
500
1000
1500
2000
2500
3000
If w
e h
ea
t t
he
mix
ture
of (M
on
oxid
e +
oliv
ine
) a
t 3
0 w
t %
Mg
O a
nd
30
wt
% S
iO2
fro
m 2
5 o
C b
y 1
50
0 J
/g, th
e
mix
ture
be
co
me
s m
ixtu
re o
f (liq
uid
sla
g +
oliv
ine
) a
t
about 1425 o
C.
2011 Montreal Montreal
2012
Enthalpy diagram: phase change with H
Ferrous Processing 202
125 oC
225 oC
325 oC
425 oC
525 oC
625 oC
725 oC
825 oC
925 oC
1025 oC
1125 oC
1225 oC
1325 oC
1425 oC
1525 oC
1625 oC
1725 oC
1825 oC
1925 oC2025
oC2125
oC2225
oC2325
oC
Orthopyroxene + AOlivine
AMonoxide + AOlivine
ASlag-liq + AOlivine
ASlag-liq
ASlag-liq + AOlivine + SiO2(s4)
ASlag-liq + AClinopyroxene + AOlivine
AOlivine + SiO2(s4)
ASlag-liq + AMonoxide + AOlivine
MgO - FeO - SiO2
SiO2/(MgO+FeO+SiO
2) (g/g) = 0.4, 1 atm
MgO/(MgO+FeO+SiO2) (g/g)
H -
H25 C
(J
/g)
0 0.1 0.2 0.3 0.4 0.5
0
500
1000
1500
2000
2500
3000
2011 Montreal Montreal
2012
Montreal
2012
Oxygen partial pressure control using Dew-point control
N2-5%H2
Ice(H2O(s)), T= -30°C
PO2=?
Oxidation ?
H2 + 1/2O2 = H2O
Annealing T= 800°C
Hot Dip Galvanizing
Cold worked at 300 °C
Dew point
Ferrous Processing 203
2011 Montreal Montreal
2012
Montreal
2012
We should select real gas to obtain
accurate Gibbs energy and volume
fraction of gas at low temperature
and high pressure.
N2-H2 gas with -30C dew point
Ferrous Processing 204
2011 Montreal Montreal
2012
Montreal
2012
We will heat this gas at 800°C using
stream file.
N2-H2 gas with -30C dew point
Ferrous Processing 205
2011 Montreal Montreal
2012
Montreal
2012
Creating stream file
N2-H2 gas with -30C dew point
Ferrous Processing 206
2011 Montreal Montreal
2012
Montreal
2012
Final partial pressure of oxygen
N2-H2 gas with -30oC dew point 800oC
Ferrous Processing 207
2011 Montreal Montreal
2012
Montreal
2012
Dew Point = 0
o C
-10o C -20
o C-30
0 C-40
o C-50
0 C
TemperatureoC
log
PO
2, b
ar
500 600 700 800 900 1000 1100 1200
-35-34
-33
-32
-31
-30
-29
-28
-27
-26
-25
-24
-23
-22
-21
-20
-19
-18
-17
-16
-15
Dew points – PO2/T Relationship
95%N2,5%H2
Dew Point 0o C
-100 C
-20o C
-30o C
-40o C
-500 C
Temperature0C
log p
O2,b
ar
500 600 700 800 900 1000 1100 1200
-35-34
-33
-32
-31
-30
-29
-28
-27
-26
-25
-24
-23
-22
-21
-20
-19
-18
-17
-16
-1590%N2,10%H2
Ferrous Processing 208
2011 Montreal Montreal
2012
Montreal
2012
Phase diagram PO2 – T: Oxidation of Fe-1%Mn-1%Si
Ferrous Processing 209
2011 Montreal Montreal
2012
Montreal
2012
BCC_A2
BCC_A2 + FCC(c,n)
FCC(c,n)
Rhodonite + BCC_A2 + SiO2(s2)
Rhodonite + BCC_A2 + SiO2(s)
Rhodonite + BCC_A2 + SiO2(s4)
Rhodonite + FCC(c,n) + SiO2(s4)
AOlivine + BCC_A2
AOlivine + BSpinel
Rhodonite + BCC_A2
Rhodonite + BCC_A2
O2 - Fe - Mn - Si
mass Mn/(Fe+Mn+Si) = 0.01, mass Si/(Fe+Mn+Si) = 0.01
T(C)
log
10(p
(O2))
(atm
)
500 600 700 800 900 1000
-40
-36
-32
-28
-24
-20
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FCC + BCC
FC
C +
BC
C +
SiO
2
FCC + BCC + SiO2 + MnSiO3
FCC + BCC + MnSiO 3
FCC + BCC + Mn2SiO4
FCC + BCC + MnSiO3 + Mn2SiO4
Fe - C - Mn - Si - O2
800oC, p(O
2) = 10
-27.5 bar, C = 0.1%
wt% Mn
wt%
Si
0.0 0.5 1.0 1.5 2.0
0.0
0.5
1.0
1.5
2.0
Drawing of the diagram:
1) Collect all blue/red/green lines at different PO2 and superimpose them in one diagram.
2) The boundary of each color line (different phase) is the phase boundary of the primary
oxide phase in the diagram.
EX17-3. Primary oxide formation diagram
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Fe-Mn-Si at PO2=10-28atm, T=800°C
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Boundaries for oxide phase
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<BCC + SiO2>
<BCC
+ MnSiO3>
wt %Mn
wt
%S
i
0.0 0.5 1.0 1.5 2.0 2.5 3.00.0
0.5
1.0
1.5
2.0
2.5
3.0
<BCC +FCC
+ MnSiO3>
<BCC +FCC
+ Mn2SiO4>
(A)(B)
(C)
Mn = 0.5
Si = 1.5
Primary oxidation Secondary oxidation
Mn = 0.5
Si = 1.0
SiO2 formation
Si depletion
in metal
SiO2+MnSiO3 formationSiO2
MnSiO3
<BCC + SiO2>
<BCC
+ MnSiO3>
wt %Mn
wt
%S
i
0.0 0.5 1.0 1.5 2.0 2.5 3.00.0
0.5
1.0
1.5
2.0
2.5
3.0
<BCC +FCC
+ MnSiO3>
<BCC +FCC
+ Mn2SiO4>
(A)(B)
(C)
Mn = 0.5
Si = 1.5
Primary oxidation Secondary oxidation
Mn = 0.5
Si = 1.5
SiO2 formation
Si depletion
in metal
SiO2+MnSiO3 formationSiO2
MnSiO3
Primary and Secondary Oxidations
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Oxidation phase diagram of the Fe-0.002%C-Mn-Si steel at 800oC
Oxidation phase diagram
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Slag/Steel/Inclusion Reactions
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Slag
Steel
Inclusion
• In FactSage, if we put slag, steel and non-metallic inclusion
together and do calculations, it is impossible to distinguish
the slag and non-metallic inclusion phase.
• Theoretically, the slag and inclusion composition should be
identical if the entire system is in equilibrium. However, the
inclusion typically formed by the deoxidation of molten steel
take a time to be completely in equilibration with molten
slag.
• The only option to see the interaction between slag and
inclusion is to do two separate calculations, ‘Slag/Steel’ and
‘Steel/Inclusion’, and Steel can be shared between the
calculations. Therefore, the influence of Slag to Inclusion
chemistry can be calculated indirectly through the change of
Steel chemistry.
• In this calculations, the molten steel after the reaction with
molten slag should be stored as a mixture (stream) for the
input for next calculations with inclusion.
• Or, the calculations can be performed using the FactSage
macro processing simulation.
2011 Montreal Montreal
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2012
SiO2( + 15%Al2O3)
CaO( + 15%Al2O3) MnO( + 15%Al2O3)Weight percent
1531
1291
1290
1667
1464
1274
1151
1573
Monoxide
Ca2SiO4 s.s.
Ca2Al2SiO7
Wollastonite
CaAl2Si2O8
SiO2
Al6Si4O13
Liquid Slag
Mn3Al2Si3O12
Ca3Si2O7
2300
22002000
1800
1600
1400
1150
1400
1200
1150
1150
1600
1020304050607080
10
20
30
40
50
60
70
80
80
70
60
50
40
30
20
10
([Mn]+[Si]) = 1wt%
1550oC
[C] = 0.7wt%
Mn/Si = 2.0
1200
Top-Slag Composition
55CaO-15Al2O3–30SiO2 (wt%)
Slag
Steel
Inclusion
Modification of inclusion in LF by interaction with top slag
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Slag/Steel/Inclusion Reaction: Macro processing Input Excel file
Slag
Steel
Inclusion
(1)
(2)
T = 1600C
10 times iterations for (1) and (2) rxns.
System temperature
Relative amount is important for the change of
inclusion chemistry
Macro process files will
be provided separately
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Slag/Steel/Inclusion Reaction: Macro processing Input Excel file
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Reoxidation of Al killed Ti bearing steel: macro-processing
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Ladle slag with 5% FeO
Reoxidation by high FeO ladle slag (for example, just after RH process)
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Reoxidation of Al killed Ti bearing steel: macro-processing
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Solid Al2O3 form after deoxidation.
Then, it is changed to liquid inclusion
with reoxidation by the slag.
The liquid inlcusion is composed mainly
Al2O3-TiO2-Ti2O3-MgO in early stage
and the CaO content in the liquid
inclusion is increasing with time.
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Reoxidation of Al killed Ti bearing steel: macro-processing
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Tundish slag with 40% SiO2
Reoxidation by high SiO2 tundish slag (in Tundish)
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Reoxidation of Al killed Ti bearing steel: macro-processing
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Solid Al2O3 form after deoxidation.
Then, it is changed to liquid inclusion
with reoxidation by the slag (more slowly
changed than the previous case).
The liquid inlcusion is composed mainly
Al2O3-TiO2-Ti2O3-MgO (less MgO than
the previous case) in early stage and
the CaO content in the liquid inclusion is
increasing with time. Ti2O3 level is
higher than previous case
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Viscosity Calculation: S+L mixtures (Einstein-Roscoe Eq.)
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Einstein-Roscoe Equation (one of the most well-accepted
equation of viscosity for solid+liquid mixture)
Viscosity (solid+liquid mixture) Viscosity(liquid) (1 solid fraction)-2.5
Original Einstein-Roscoe equation use ‘volume fraction of solid’
instead of ‘solid fraction’ and correction term for morphology,
but all these values are not very well-known for general solids,
we can simply use the solid fraction (wt fraction) for this
equation as approximation.
This value can be calculated using “Equilib” module at
given system composition and temperature (Step-1).
Viscosity of liquid slag can be
calculated from “Viscosity”
module from slag composition
calculated from “Equilib” (Step-2)
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Viscosity Calculations “Step-1”: Composition of liquid slag
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Viscosity Calculations “Step-2”: Viscosity of liquid slag
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Composition of liquid
slag from Equilib
Take these results
for next step
“Melts” database is for liquid slag
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Viscosity Calculations “Step-3”: Liquid + Solid mixture
Ferrous Processing 228
Amount
of slag
Amount of solids
(100-amount of liquid)
Step-2
Einstein-Roscoe
Eq.
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Steelmaking Process: Thermodynamic Database
Thermodynamic Database Development for Steelmaking process
Database for De – P Slag / Flux development (2009~ 2014) • CaO-FetO-SiO2-MgO-MnO-Na2O-Al2O3-P2O5-CaF2 database • Slag / Solid phases • Experiment for phase diagrams • for the applications to Hot metal treatment and Basic Oxygen Furnace process
Database for Steel refining slag and Casting mould flux containing Fluorine (CaF2) (2009~2014) • CaO-MgO-Al2O3-SiO2-Na2O-Li2O-F (CaF2, NaF, LiF) database • Slag / Solid phases • Experiment for phase diagrams • for the applications to the optimization of mould flux and CaF2 containing flux
Steelmaking consortium project (2009 ~ 2014) with the support of