Ferrous applications I - CRCT...Ferrous Applications I 3 Contents Simple examples of various functions of Phase Diagram module Binary phase diagram: CaO-SiO 2 Slide #75 Ternary phase

Ferrous Applications I 1

Ferrous Applications I


Contents

Simple examples of various functions of Equilib module

Target/Transition Simple transition calculation,

Formation target, Precipitation target

Composition target

Slide # 5

Stream & Heat

balance

Creating stream for liquid steel & heat balance during alloying process Slide #13

Open Vacuum degassing of steel Slide #18

Fixing partial

pressure or activity

Fe2+ and Fe3+ amounts in slag,

Gas solubility in slag

Oxidation of Fe

Slide #23

Composition target Calculate amount of specific reactant to get a certain final composition

(de-sulfurization of steel with CaSi flux)

Slide #31

Table calculation Multiple calculations with random input composition Slide #34

“I” and “J” options Possible immiscibility in a solution phase:

(Ti,Nb)(N,C) formation from HSLA (high-strength low-alloy) steel

Slide #40

Scheil cooling Cooling microstructure: Slag and TWIP steel cooling Slide #44

<A> variable Interface reaction: refractory / slag interaction (corrosion of refractory) Slide #55

Thermodynamic

properties

Activity calculations in binary system, Ternary iso-activity line calculation,

Activity of oxygen in liquid Fe, and dH, dS, dG calculations

Slide #59


Contents

Simple examples of various functions of Phase Diagram module

Binary phase diagram: CaO-SiO2 Slide #75

Ternary phase diagram: CaO-Al2O3-SiO2 Slide #77

Oxidation diagram of Fe-Cr-O2 Slide #81

Predominance diagram / Fe-Mn-O2-S2 Slide #83

FeO-SiO2 at Fe saturation Slide #88

FeO-SiO2 with fixed partial pressure of O2 Slide #90

FeO-SiO2 with fixed CO and CO2 pressures Slide #92

CaO-FeO-SiO2 diagram at Fe saturation Slide #96

CaO-FeO-SiO2-5%MgO at Fe saturation Slide #98

Applications to refractory/slag interactions Slide #100

Paraequilibrium for A3 temperature of Fe-C system / Rapid quenching Slide #105

Applications to Si steel design Slide #111


Simple calculation examples with the

Equilib module


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


Reactants Window - Fe-Si at Fe-5wt.% Si

Reactants Window

Data Search


Selection of solid phases

Pure solids

Menu Window - Fe-5wt.% Si at 1030 oC


Results Window - Fe-5wt.% Si at 1030 oC


Menu

Fe-5wt.% Si from 200 oC

to 1800 oC every 200 oC

Fe-5wt.% Si transition calculations: “Transition”


Phase transformation calculations

• “Transition”:

– select “Transition” for calculation mode.

– simplest way to calculate all transitions of T or X over a given range set by user.

for X (composition), set <A> for component in Reactant window.

– FactSage will show all conditions where transitions occur.

• “Precipitation” target:

– Set “P” option for target phase.

– FactSage will decrease temperature and find at which temperature another

phase starts to form from the target phase. For example, if Liquid is target

phase, “P” target will give liquidus temperature.

• “Formation” target:

– Set “F” option for target phase.

– FactSage will increase temperature and find at which temperature the target

phase begins to form. For example, if Liquid is target phase, “F” target will give

solidus temperature.


Fe-5wt.%Si target for liquid phase: “Formation target”

F – formation target phase


Fe-5wt.%Si target for liquid phase: “Precipitation target”

P – precipitate target phase


Stream

• What is a “stream” and why we need it? In industrial processes, solutions (or mixtures) can be added as reactants.

This is called a “stream” (or “mixture”) in FactSage. In order to easily create

and add such solutions as input, a “stream” can be created from Equilib and it

can be added as a reactant for the next Equilib calculation. Heat and mass of

solution(s) are conserved in a stream.

* a “mixture” can be created with the “Mixture” module in FactSage

Equilib #1

Equilib #2

Equilib #3 Phase #1-2

Phase #1-1

Phase #2-1

Phase #2-2

(100%)

(60%)

Additional

component


Creating a new stream : Fe-0.1C-1Mn-1Si at 1600oC


Save the liquid FeLQ

phase as a stream

Creating a new stream : Fe-0.1C-1Mn-1Si at 1600oC


Import the stream : Fe-0.1C-1Mn-1Si at 1600oC

For heat balance, “Initial condition”

should be selected.

This is the temperature and pressure of the stream

when it was created. Streams with the same stream #

always have the same T and P.


Heat balance: Fe-0.1C-1Mn-1Si(1600oC) + Al (25oC)

Adiabatic calculation :

Delta(H) = 0

Delta(H) > 0: heat loss

Delta(H) < 0: heat gain

Calculated adiabatic

temperature = 1605.5 oC


Open calculation

• What is “open” and why we need it? In many industrial processes, gas is continuously injected and gas is emitted

after reaction with the materials in a reactor.

This process can be simulated by the “Open” calculation mode.

To activate this, <A> for gas species should be assigned in the Reactant

window.

<A> Gas reactant(s) Equilibrium

reaction

Repeat this calculation for “Step” times and calculate the evolution of the

chemical composition of gas and materials in the reactor

No heat balance calculation can be done. Temperature of reactor should be

specified by user. Reaction in reactor reaches full equilibrium at each step.

Liquid steel

Gas product(s)


RH – Vacuum degassing process

Open Calculation - off-gas removal

Stream Fe-0.1C-1Mn-1Si + O2

at 1600oC and 0.01 atm


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


1

2

3

Open Calculation - Plot of log(wt% liquid steel)


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


Fixing activity of gas or other phase

When we need to fix the activity or partial pressure ? Only a couple of cases when you need to fix activity or partial pressures are listed

below. There could be numerous cases other than these.

• In steelmaking processes or other pyrometallurgical processes, “Slags” play

important roles. Slags can contain oxide components having more than 2 oxidation

states (for example, iron oxide, FeO and Fe2O3). In some case, FactSage cannot

determine how much Fe2+ and Fe3+ exist in molten slags. The best way to resolve

this problem is to fix the oxygen partial pressure.

• Any case when you have oxides (solid or liquid state) with more than 2 oxidation

states, it is better to fix oxygen partial pressure.

• When you study the solubility of gas species in slag (for example sulfur), it is better

to fix the partial pressure of S2 or SO2 gas as in experiments.

• If you equilibrate liquid steel (containing O or S) and slag, this can automatically

fixing the oxygen or sulfur partial pressure. So, you don’t have to fix the partial

pressure of the gas species.

• If you want to saturate the slag with Fe, you can fix the activity of Fe = 1 or enter

small amount of Fe in the calculations.

• If you want to calculate for iso-activity of SiO2 (or any other component of the slag),

you can set activity of SiO2.


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 or solid species

3

1


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



Fixed pO2 in MgO-FetO-SiO2 slag




The amounts of FeO and Fe2O3 change with PO2




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


Gas / Slag (CaO-MgO-FeO-SiO2) / Liquid Fe equilibration

Fixed partial pressure of a gas : Fe saturation and fixed SO2 pressure


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 pressure


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


Add CaSi (<A>) to reduce [%S] in Fe-LIQUID to 0.002%.




Amount of CaSi = 0.96 gram to obtain [%S] = 0.002%


Table calculations: multi-calculation using EXCEL spreadsheet

For example, calculation of liquidus temperatures for many slag compositions

One by one in Equilib using Precipitation target for liquid slag

Or using Table calculation

Perform one calculation first to make

sure that your calculation is working



Activation of Table

Check the order of inputs

This order is very important !!



Prepare data in Excel spread sheet (input order is the same as the input

displayed in FactSage Table mode; see previous slide)

and then save it as “txt” file



Import table from text file



Close Table input mode

Now in the calculation, activate “Table”



If you “calculate”, four calculations are performed:

Each tab shows the results of each input

You can save the results in Excel format


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


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 immiscible phases.

J option for FCC phase: Fe steel containing (Ti,Nb)(C,N) ppts


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)


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


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


Equilibrium cooling of a CaO-SiO2-Al2O3-MgO slag

Equilibrium solidification of slag


Equilibrium solidification of a slag: plot amount vs. temperature

2

1

3

4

5


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


T(C)

gra

m

1000 1100 1200 1300 1400 1500 1600

0

020

040

060

080

100


Equilibrium solidification is completed at ~ 1410oC


Scheil cooling solidification of a slag

Scheil cooling of a CaO-SiO2-Al2O3-MgO slag

Scheil cooling temperature setup:

(initial_T final_T)


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


T(C)

gra

m

1225 1275 1325 1375 1425 1475 1525 1575

0

020

040

060

080

100


Scheil cooling solidification is completed at ~ 1320oC


Solidification of mould flux

Using ‘CON1’ database


Equilibrium cooling of Fe-20Mn-1C-1Al TWIP steel

Equilibrium solidification of steel: TWIP steel


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


Scheil cooling solidification of steel: TWIP steel

Scheil cooling of Fe-20Mn-1C-1Al TWIP steel


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 with an equilibrium

calculation.


Simple counter / cross inter-diffusion calculation: <A> option

Counter/cross inter-diffusion reactions at an 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


Counter / cross reaction: refractory / slag

Slag

60%CaO-40%SiO2

Refractory

95%Al2O3-5%MgO


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


[Sla

g]

[Re

fra

cto

ry

]

A l2O

3

F e O

M g O

C r2O

3

(1 -x ) r e fr a c to r y + x s la g (b y w e ig h t)

co

mp

os

itio

n o

f s

pin

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

1 0

2 0

3 0

4 0

5 0

6 0

7 0

8 0

9 0

1 0 0

[Refractory]

[Slag]

Spinel

Periclase

[Sla

g]

[Re

fra

cto

ry

] S la g

P e r ic la s e

S p in e l


re

lati

ve

am

ou

nt

of

ea

ch

ph

as

e,

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

1 0

2 0

3 0

4 0

5 0

6 0

7 0

8 0

9 0

1 0 0

A l2O

3

F e O

M g O

C r2O

3

[Sla

g]

[Re

fra

cto

ry

]


co

mp

os

itio

n o

f p

er

icla

se

, w

t%

-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

1 0

2 0

3 0

4 0

5 0

6 0

7 0

8 0

9 0

1 0 0

[Sla

g]

[Re

fra

cto

ry

]

C a O

S iO2

A l2O

3

M g O

F e OC r

2O

3


co

mp

os

itio

n o

f s

lag

, w

t%

-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

1 0

2 0

3 0

4 0

5 0

6 0

7 0

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.


Application: Activity calculations

Slag: binary, ternary and multi-component systems

FeLq : oxygen and alloying elements

In FactSage 7.0, iso-activity lines in ternary or higher order

systems can be easily calculated using the Phase Diagram module


Activity calculations – Binary system


Activity calculations – Binary system

Activity with respect to solid or

liquid standard state) ?


Activity calculations – Ternary system

Calculation of iso-activity line of SiO2

in the CaO-MgO-SiO2 system



Save results in Excel

or spread sheet format



Plot the results in triangular diagram

- Prepare the triangular frame

- Plot the A,B,C coordinates in triangular diagram


Activity calculations – Quaternary or higher-order systems

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.


Activity calculations – Quaternary or higher-order systems

A. Draw phase diagram of A-B-C with fixed D, and check manually the iso-activity

points of A in phase diagram mode

B. Calculate activity of A in entire A-B-C diagram with fixed D section and manually

connect iso-activity points of A.

In future, iso-activity calculation mode will be added to the Phase Diagram module.


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 is in Kelvins

)state.stdHenrian(aM

M100)state.std%wt(a

i

Fe

i

i

( H e n r ia n S .S . ) ( u re e le m e n t S .S . )

( . .) ( . . )

R T ln γ g g

γ

o o o

M M M P

o

M p u re e le m e n t S S M M H e n ria n s sa a

5.3/15280ln Tγo

O

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



aO in FeLq

Total dissolved Al and O

Dissolved Al, O, Al*O, Al2*O


aO in FeLQ Total dissolved Al and O

Dissolved

unassociated O


Then, convert aO in FeLq to aO wt% s.s.


Thermodynamic properties: ΔG, ΔH, ΔS etc.

Initial conditions for phase

and temperature should be

specified

For calculating the difference of thermodynamic

properties from the initial state to the final state,

“Initial Conditions” should be activated.


Thermodynamic properties: Activity, ΔG, ΔH, ΔS etc.


Thermodynamic properties: ΔG, ΔH, ΔS etc.


Thermodynamic properties: Activity, ΔG, ΔH, ΔS etc.


Simple examples of Phase Diagram

Calculations

Binary phase diagrams

Ternary and multi-component diagrams


There is a stable miscibility gap in slag; automatic selection by FactSage

Binary phase diagram: CaO-SiO2


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


Ternary phase diagram: CaO-SiO2-Al2O3 isothermal section


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 + 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


SiO2

CaO Al2O3

1:1

Ternary system: section across ternary (isopleth)


ASlag-liq

ASlag-liq + Al2O3(s4)

ASlag-liq + CaAl12O19(s)

ASlag-liq + Ca2Al2SiO7(s)


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 across ternary (isopleth)


Oxidation diagram: Fe-Cr-O2

Combination of many databases:

FactPS (FACT53): gases

FToxid: oxide phases

FSstel: fcc, bcc and other metallic phases


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


Predominance diagram: Fe-Mn-O2-S2

Combination of many databases:

FactPS (FACT53): gases

FToxid: oxide phases

FSstel: fcc, bcc and other metallic phases


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


This is NOT a 10% Al2O3 section !!

Quaternary diagram: iso-composition section


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 set Al2O3 = 0.11111 Al2O3 = 10%

2) Click here

= 10% Al2O3

This is 10% Al2O3 section !!

1) Equilib calculation mode

Quaternary diagram: iso-composition section


Quaternary system: CaO-Ca2SiO4-MgAl2O4


Iron oxide containing system: Fe saturation

Intentional addition of Fe to give Fe saturation


Iron 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 give Fe saturation


Iron oxide containing system: fixed PO2

Fixing PO2 to control the

oxidation state of Fe


Iron oxide containing system: fixed PO2

Fe2O3(s) + SiO2(s2)

ASpinel + SiO2(s2)

ASpinel + SiO2(s4)

Fe2SiO4(s) + 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 temperatures and compositions


Iron oxide containing system: fixed CO/CO2 gas ratio

Select only CO, CO2 and O2 gas to simulate a real experiment of oxide/gas equilibration.

If we select all gases, some amount of oxides may evaporate depending on the relative amounts of

gas and oxide in the calculations

Fixing PO2 by CO/CO2 gas mixture



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






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 + 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

1 mole

Fe2O3

1 mole

CO-CO2 gas

<Closed system>

1mole

Fe2O3

10 mole

CO-CO2 gas <Closed system>

1 mole

Fe2O3

10 mole CO-CO2 gas

<Open system>


CaO-FetO-SiO2 system at Fe saturation


CaO-FetO-SiO2 system at 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 + a-Ca2SiO4 + Fe(liq)

CaO - FeO - SiO2 - Fe

1650oC, Fe/(CaO+FeO+SiO

2) (g/g) = 0.001


CaO-FetO-SiO2-5wt%MgO system at Fe saturation

In the FactSage Phase Diagram module, special

attention is required for the axis setting of

quaternary or higher-order systems.

The first three components are always taken as

A,B,C axes with respect to one mole of (A+B+C).

Therefore, to calculate a 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 input value for FactSage


CaO-FetO-SiO2-5wt%MgO system at 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)


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


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 contents at 1650oC.

At 20% CaF2: Slag can be directly equilibrated with CaO (no Ca2SiO4)

Using ‘CON1’ database

Change of Ca2SiO4 saturation

composition with CaF2 content


CaO-Al2O3-SiO2 slag – MgAl2O4 refractory

50%CaO-30%SiO2-20%Al2O3 slag in moles: (CaO)0.5618(SiO2)0.3146(Al2O3)0.1236

(Equilib or Phase Diagram components are on a molar basis)

ASlag-liq

ASlag-liq + ASpinel

ASlag-liq + ASpinel + MeliliteASlag-liq + Melilite

ASlag-liq + a-Ca2SiO4


(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


CaO-Al2O3-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 slag


CaO-Al2O3-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


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

Dissolution of MgAl2O4/MgTi2O4

refractories into slag

MgAl2O4 saturation line


Paraequilibrium

Paraequilibrium (Partial equilibrium) vs Orthoequilibrium (Full equilibrium)

Fe

C

Mn

Fe

Si

fcc bcc T

ime

Fe

C

Mn

Fe

C

Si

Fe

C

Mn

Si

Fe

C

Mn

Si

Paraequilibrium

(partial equilibrium only for C)

(Ortho)equilibrium

Diffusion of C is much faster than Mn or Si


Paraequilibrium: Steel A3 temperature


CEMENTITE + BCC_A2

CEMENTITE + FCC_A1

FCC_A1

FCC_A1 + BCC_A2

Fe - C - MnMn/(Fe+C+Mn) (g/g) = 0.02, 1 atm

C/(Fe+C+Mn) (g/g)

T(C

)

0.000 0.005 0.010 0.015 0.020

500

600

700

800

900

1000

FCC_A1

CEMENTITE + FCC_A1

CEMENTITE + BCC_A2

FCC_A1 + BCC_A2

Fe - C - Mn - paraequilibrium diffusing elements: CMn/(Fe+C+Mn) (g/g) = 0.02, 1 atm

C/(Fe+C+Mn) (g/g)

T(C

)

0.000 0.005 0.010 0.015 0.020

500

600

700

800

900

1000

Paraequilibrium: Steel A3 temperature

Full equilibrium

Paraequilibrium


Paraequilibrium: Rapid solidification to produce amorphous metal

Blank no diffusion of any element: this is what happens during rapid solidification



FC

C_A

1 +

Cu

5Z

r(s)

HC

P_A

3 +

CuZ

r 2(s

)

CuZ

r 2(s

) +

Cu

10Z

r 7(s

)

Cu

8Z

r 3(s

) +

Cu

10Z

r 7(s

)

Cu

8Z

r 3(s

) +

Cu

51Z

r 14(s

)

Cu

5Z

r(s)

+ C

u51Z

r 14(s

)

Liquid + BCC_A2

Liquid

Cu - Zr1 atm

Zr/(Cu+Zr) (mol/mol)

T(C

)

0.0 0.2 0.4 0.6 0.8 1.0

0

200

400

600

800

1000

1200

1400

BCC_A2

Liquid

HCP_A3FCC_A1

Cu - Zr - phase with minimum G1 atm

Zr/(Cu+Zr) (mol/mol)

T(C

)

0.0 0.2 0.4 0.6 0.8 1.0

0

200

400

600

800

1000

1200

1400

1600

1800

2000

Possible range for

amorphous formation

Full equilibrium

Paraequilibrium:

rapid solidification


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

Mg

Cu Zrmole fraction

Liquid

Laves_C36

BCC_A2

HCP_A3

FCC_A1

FCC_A1 BCC_A2HCP_A3

Cu - Zr - Mg - phase with minimum G

300oC, 1 atm



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


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: Fe-Si + C


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



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



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


Thanks to FactSage Steelmaking Consortium Members

Developments of

• Thermodynamic database

• Process simulation model

Training for FactSage and Process simulation

Documents

Ferrous applications I - CRCT...Ferrous Applications I 3 Contents Simple examples of various functions of Phase Diagram module Binary phase diagram: CaO-SiO 2 Slide #75 Ternary phase