Peter Mueller Sintering Lab Report

8/15/2019 Peter Mueller Sintering Lab Report

1/25

Analyzing Sintering Properties of Alumina Powder for Industrial

Applications

Peter Mueller

Lab Group WA2

February ! 2"#$

Mueller #


2/25

Abstract

%&is e'periment was performed to determine t&e sintering properties of an

alumina powder! including green density! (red density! porosity! and linear

s&rin)age! and to use t&ese properties to recommend a design and procedure for

creating a beam out of alumina* "*$$ g samples of t&e alumina powder were

measured! pressed into cylindrical pellets by a 2""" lb load! and (red for +arious

durations at #"",-! wit& t&e p&ysical dimensions of t&e samples measured during

e+ery step* It was found t&at t&e procedure used ga+e a green density of 2*2$ .

"*"$ g/cm0! and t&at (red density and linear s&rin)age +aried wit& (ring time* It

was determined t&at sintering for "*0 &ours ga+e t&e best combination of &ig&

density and limiting of grain growt&* At t&is sintering time! t&e (red density was

e'trapolated to be ~0*10 . "*" g/cm0! porosity was found to be *2$3! and linear

s&rin)age was found to be #$*03* %&ese results were found to be e'tremely

reproducible! wit& green densities only +arying by 23 and (red densities +arying by

0 to 3! depending on t&e (ring time* %&ese sintering properties were in+estigated

to assist in designing a process for creating a cantile+er beam* %&e dimensions of

t&e beam are to be "* ' "* cm in cross4section and $*$ cm long and t&e beam

must be able to support a $" g load at $ cm wit& no more t&an 5m of deflection*

6ased on t&e linear s&rin)age +alues determined! a process for creating t&is beam

was designed! wit& a die pressing down perpendicular to t&e long a'is and mold

interior dimensions of "*7 cm ' "*7 cm ' 1*1 cm* %&e ne't step for t&e company

is to test t&is con(guration for green and (red density consistency as well as

accurate linear dimensions*

Mueller 2


3/25

%able of -ontents

Introduction

8'perimental Procedure 1

9esults and Analysis 1

:esign

9ecommendations ##

Appendi' A #2

Appendi' 6 #2

Mueller 0


4/25


5/25

conformation* %&is step is &indered by t&e friction of t&e walls of t&e die and by t&e

friction between granules* %&e second and most important step is t&e deformation

of t&e granules* %&e binder is c&osen to be mec&anically wea)er t&an t&e base

material being compressed! w&ic& means t&at under compression! t&e binder will

yield (rst* %&is allows t&e powder to initially >ow li)e a larger grained powder! butt&en allows it to be compacted into spaces on t&e order of t&e smallest particle*

%&e (nal step of compression is t&e actual ceramic particles being deformed

elastically and plastically* %&is step s&ould be dealt wit& wit& care! as lea+ing too

muc& elastic strain in t&e matri' w&ile compressed can cause t&e green sample to

e'pand greatly or e+en crac) w&en released from stress* %&ese crac)s are

signi(cant because t&ey could cause t&e green samples to brea) apart before being

able to be (red* Additionally! some of t&e crac)s could remain on t&e inside of t&e

sample t&roug& t&e (ring process! pro+iding locations for crac) formation andgrowt& in t&e (red ceramic! w&ic& would signi(cantly wea)en t&e (nal product*

Figure # s&ows t&e microstructural c&aracteristics of t&e t&ree stages of powder

compression*

Figure #* Micrograp& of alumina powder undergoing compression* ;a< loose state!;b< initial alignment stage! ;c< plastically deforming (nal stage ;-ompaction<

After compression into a greenB solid! t&e ceramic is ready to be sintered! or

(redB* %&e purpose of (ring t&e solid is to raise t&e material to a temperature

w&ere it does not li=uefy! but t&e t&ermal energy is &ig& enoug& for signi(cant

di?usion to occur! allowing t&e particles to rearrange t&emsel+es into a more

t&ermodynamically stable conformation! w&ic& almost always &as a &ig&er density

Mueller $

(a) (c)(b)


6/25

t&an t&e green density* Initially! as t&e temperature rises! t&e binder burns o?! as it

is typically made of a polymeric material ;Gupta


7/25

Figure 2* Microstructure of a ceramic sample during sintering* ;a< powder compact!;b< initial sintering! ;c< intermediate stage s&owing signi(cant di?usion! ;d< (nal

stage s&owing +oid reduction ;Francis 2<

%&e competing process to densi(cation is )nown as coarsening* -oarsening

is anot&er t&ermodynamically fa+orable process in w&ic& material from one or more

grains Dump across grain boundaries to add to larger! growing grains* %&is is an

energetically fa+orable process because t&e surface area to +olume ratio for s&apes

goes down as t&e s&ape gets bigger and surface area is typically an energetically

negati+e p&enomenon* %&is increase in grain size typically &as a negati+e e?ect on

t&e (nal properties of t&e material! as grain boundaries act as barriers for

dislocation motion! strengt&ening materials* %&us! a balance between time andtemperature s&ould be c&osen to ma'imize densi(cation w&ile limiting grain

growt&* Ene way to do t&is is to not sinter a sample any longer t&an it needs to

reac& t&e desired density! as once t&e density goal is reac&ed! any e'tra time will

only worsen mec&anical properties*

Mueller


8/25

After sintering! t&e sample is allowed to cool down to a safe temperature!

during w&ic& time s&rin)age typically occurs* Any material undergoing an increase

in density w&ile )eeping t&e same mass must necessarily decrease in +olume* %&is

decrease in +olume can be represented by t&ree linear s&rin)age +alues! one for

eac& dimension* Linear s&rin)age is calculated as ΔL/L0! w&ere ΔL is t&e c&ange inlengt& of t&e dimension and L0 is t&e original lengt& of t&at dimension* If t&e green

solid is created wit&out large density gradients! t&e linear s&rin)age s&ould be

largely isotropic* nowing t&e s&rin)age allows for t&e dimensions of a die to be

increased so as to lea+e a correctly4sized part after s&rin)age* %&e e=uation used

for t&is is!

9e=uired :imension H Desired Dimension /(1− ΔL

L0

). ;#<

As noted pre+iously! t&e strengt& of a sintered ceramic will +ary wit& its (red

density* %o design a ceramic part using sintering! t&is relations&ip must be )nown*

Ene e=uation found to model t&is relations&ip for sintered alumina is gi+en by

E H #"e40*1P! ;2<

w&ere E H elastic modulus of t&e alumina and P H +olume fraction of pore ;Francis

#


9/25

wit& a piece of paper used to transport t&e powder ;MS

remo+ed from t&e die! weig&ed as before! and t&e diameter and t&ic)ness were

measured using a General model # &and calipers wit& a resolution of "*"# mm

;#&ours! respecti+ely! before being cooled to under #"",- o+er a period of 04$ &ours*

Finally! t&e sintered pellets were again weig&ed and t&eir diameter and t&ic)ness

measured* Additionally! t&ere was a sample of double mass! #*# g! produced using

t&e e'act same procedure and sintered for #*2 &ours*

General lab safety procedures were followed in t&e labC speci(cally! safety

glasses were worn at all times to pre+ent eye inDuries! and care was ta)en to a+oid

unnecessary in&alation of alumina powder fumes! w&ic& could potentially cause

minor respiratory irritation*

9esults and Analysis

An important topic of analysis for any production process is t&e

reproducibility of t&e results* In t&is process! t&e imprecise nature of doing t&e

measuring and die4(lling by &and means t&at t&is is t&e step of t&e process most

li)ely to su?er from reproducibility problems* %o e'amine t&e consistency of t&e

green pellet production process! t&e mass! t&ic)ness! diameter! and from t&ese t&e

green density! were measured or calculated* %&e student t4distribution multiplier of

2*#0#! corresponding to t&e #1 pellets measured was used to generate $3

con(dence inter+als for eac& c&aracteristic! and t&e results are gi+en in %able #*

Mueller


10/25

%able #* Green pellet $3 con(dence inter+als for mass! t&ic)ness! diameter! and

calculated density

-&aracteristi

c

Lower 6ound Mean @pper 6ound

Green Mass;g<

"*$"# 0.528 "*$$$

%&ic)ness

;mm<

#*$ 1.83 #*#

:iameter

;mm<

#2*1 12.76 #2*70

:ensity

;g/cm0<

;calculated<

2*2" 2.25 2*0"

%&ese calculations s&ow t&at t&e density of t&e green pellet will be accurate to

wit&in "*"$ g/cm0! or roug&ly 23! of t&e mean $3 of t&e time! w&ic& is an

e'cellent result gi+en t&e &andmadeB =uality of t&e process* Additionally! t&e

indi+idual measurements s&owed t&at for t&e #1 samples produced! t&e a+erage

de+iation from t&e mean was less t&an #3! s&owing a similarly tig&t distribution of

results* It was determined t&at random error dominates in t&is e'periment! as t&e

random error dwarfed systematic error! e+en wit& #1 samples being tested* %&e

sources of systematic error were t&e starting mass of t&e powder! t&e green mass!

and t&e pellet t&ic)ness* 6ot& of t&e mass measurements were accurate to wit&in

"*""# g and t&e &and calipers used to measure t&e t&ic)ness of t&e pellet was

accurate to wit&in "*"# mm* %o reduce t&e error on t&e t&ic)ness measurements!

t&e t&ic)ness of eac& pellet was measured 0 times and a+eraged to determine a

(nal +alue* As noted! t&e combined error from t&ese t&ree systematic error sources

was +astly lower t&an t&e random error present in t&e e'periment* %&e parameter

most responsible for t&e +ariations in measurement was t&e t&ic)ness of t&e pellet!

w&ic& was dependent on t&e o+erall mass placed in t&e die* %&is ma)es sense as

t&e diameter of t&e die is ('ed! causing any +ariations in total +olume to be

accounted for in t&e t&ic)ness of t&e pellet* %&ere was no discernable correlation

between starting mass and pellet t&ic)ness for t&e "*$$ g samples! li)ely due to t&e

e'tremely small di?erences in starting mass* E+erall! t&is is an issue for sizing t&e

indi+idual sample! but &ad no noticeable e?ect on density* %&is can most clearly be

Mueller #"


11/25

seen on t&e double weig&t sample! w&ic& was produced following t&e e'act same

speci(cations e'cept double t&e mass of powder* %&e pellet of t&is sample &ad

roug&ly double t&e t&ic)ness and double t&e mass of t&e normal pellets but &ad t&e

same density! being less t&an #3 less dense t&an t&e mean* %&is result is actually

closer to t&e mean t&an many of t&e normal pellets! s&owing t&at t&e o+erall massor t&ic)ness of t&e sample &as little e?ect on t&e density after compaction* It was

e'pected t&at t&e double mass sample would &a+e a density e=ual to or slig&tly less

t&an t&e ot&er samples! as t&e /: ratio increases! decreasing t&e e?ecti+e load on

t&e die as frictional losses increase* In t&is case! t&e /: ratio was still relati+ely

low! so t&e lac) of a di?erence in density is not surprising*

In general! green densities for ceramics are typically in t&e range of $$3 to

1$3 of t&eoretical density ;Sc&oenberg! Sun

&ard on t&e Mo&s &ardness scale ;Aluminium


12/25

Firing time ;&ours< Lower bound Mean @pper bound" 0*2 3.30 0*01

"*# 0*0 3.55 0*1"*1 0*1 3.67 0*##*2 0*$$ 3.70 0*7

Additionally! Figure 0 s&ows density plotted against (ring time to s&ow t&e

diminis&ing returns of density as (ring time increases* It is clear t&at t&e density of

t&e (nis&ed ceramic rises as t&e sintering time goes up! but t&is process slows

considerably past roug&ly "*0 &ours*

4"*2 " "*2 "* "*1 "*7 # #*20

0*#

0*2

0*0

0*

0*$

0*1

0*

0*7

Fired :ensity +s* Sintering %ime

Firing time ;&ours<

Fired :ensity ;g/cm0<

Figure 0* Fired density +s sintering time* Four samples were created and sintered at

eac& sintering time

%&e mass lost by t&e pellets during t&e sintering process was "*"#$ . "*""#

grams! w&ic& is 2*73 of t&e original a+erage pellet mass of "*$27 g* %&e

t&ermogra+imetric analysis of t&e powder gi+en in t&e design memo s&owed a mass

loss of~

03! w&ic& matc&es =uite closely t&e mass loss as a percentage of t&eoriginal pellet mass ;Francis #


13/25

range for t&e t&ic)ness measurement t&an t&e diameter measurement! as can be

seen in %able 0* %&is is a result of t&e diameter of t&e mold being ('ed! w&ile t&e

t&ic)ness was a function of t&e +olume of powder put into t&e mold* Any di?erence

in initial powder +olume was ta)en up as a t&ic)ness di?erence! leading to

signi(cant error range! w&ile t&e diameter was essentially unc&anging! leading toalmost no error at all*

%&ese diameter and t&ic)ness measurements ta)en in t&e lab allowed for t&e

linear s&rin)age to be determined* %&e +alues found are gi+en in percentages in

%able 0* As would be e'pected! t&e s&rin)age was greater for longer sintering

times! as t&ese longer times led to a larger o+erall s&rin)age and a &ig&er density*

An interesting note is &ow similar t&e t&ic)ness and diameter s&rin)ages are!

generally wit&in #3 of eac& ot&er! indicating t&at t&e material is essentially

isotropic* nowledge of t&e s&rin)age rates is )ey to designing a die for productionof a sintered ceramic part! as failing to account for s&rin)age will lead to an

undersized part and incur signi(cant retooling costs* It s&ould be noted t&at t&e

s&rin)age +alues are +ery +ariable and t&is must be ta)en into account w&en

designing a die to produce a speci(c part using t&ese met&ods*

%able 0* Linear s&rin)age of sintered alumina powder samples for di?erent sintering

times

:iameter s&rin)age ;3< %&ic)ness s&rin)age ;3


14/25

%&e diameter and t&ic)ness s&rin)ages were also larger t&an t&e a+erages for "*#

&ours! indicating t&at t&e double mass pellet underwent signi(cantly more

densi(cation t&an t&e ot&er pellets* %&is disco+ery could potentially be useful in t&e

design of t&e cantile+er beam in t&at t&e beam creation setup could be designed to

be more li)e t&e double mass pellet t&an t&e ot&er pellets* Speci(cally! t&esintering could ta)e place wit& t&e beam oriented wit& t&e long side +ertical! to

allow gra+ity to cause more compaction! w&ic& seems li)e t&e most li)ely

e'planation for t&e greater density*

An S8M was used to image t&e surface of t&e sintered pellets to determine

surface properties! w&ic& are gi+en in %able * %o analyze t&e images! a small grid

was drawn on t&e surface on t&e same scale as t&e scale gi+en in t&e image! and

t&e a+erage +alue of eac& c&aracteristic found was determined* %&e properties

found were a+erage grain size! a+erage pore size! and a+erage pore content* %able * Surface c&aracteristics determined from analysis of S8M images

Firing time

;&<

A+erage Grain Size

;5m<

A+erage Pore Size

;5m<

A+erage Pore -ontent

;3<" "*2$ "*$# 2"*# "*02 "* 1#"*1 "*$0 "*2 00#*2 "*7# "*#2

Figure * S8M image of unsintered alumina sample! s&owing

Mueller #


15/25

grid drawn on image to analyze surface properties

Figure s&ows an e'ample of t&e S8M images! wit& t&e grid drawn on to allow for

areal analysis* %&e a+erage grain size was determined by estimating t&e size of as

many grains as could be clearly identi(ed and a+eraging t&em* A+erage pore size

was done in t&e same manner! wit& pores generally being de(ned as t&e areas

between grains* Pore content was found by estimating t&e percentage of t&e top

plane made up of grains and subtracting from #""* All of t&ese +alues were +ery

roug& estimates! as t&e planes of t&e image are &ard to discern and t&e grains are

irregular in size and s&ape*

:esign

%&e memo for t&is e'periment calls for t&e design of a beam to support a

cantile+ered load wit&out e'cessi+e elastic deformation* %&e re=uired dimensions

for t&e beam are "* cm ' "* cm ' $*$ cm and t&e beam must be able to support a

load of $" g at $ cm wit& no more t&an m of +ertical de>ection ;Francis #ection in a beam is

νc= P L

3

3 E I z ! ;2<

w&ere νc is t&e +ertical de>ection! P is t&e load! L is t&e distance from t&e support to

w&ere t&e load is applied! E is t&e elastic modulus of t&e beam! and I z is t&e polarmoment of inertia of t&e beam* Sol+ing t&is e=uation for 8 gi+en νc H ' #"41 m! P

H "*"$ ! L H "*"$ m! and I z H widt&Nt&ic)ness0/#2 H 2*#00 ' #"4## m!

gi+es a minimum E of 20*$ GPa* %o e?ecti+ely use t&is +alue in an engineering

application! t&e elastic modulus of a porous! sintered alumina sample must be

)nown* An e=uation for determining t&e elastic modulus of a porous alumina

ceramic is gi+en!

E=410e−3.96 P ! ;0<

w&ere 8 is t&e elastic modulus in GPa and P is t&e +olume fraction of pores in t&e

sintered ceramic ;Spriggs


16/25

would &a+e to be 71*23 alumina and t&us &a+e a density of "*712N g/cm0 H

0*1 g/cm0 to meet t&e re=uirements of t&is cantile+ered beam*

Figure #! s&owing t&e relations&ip between sintering time and density of

samples! was used to determine an optimal sintering time for t&e cantile+er beam*

As all of t&e samples sintered for "*# &ours &ad a density comfortably abo+e 0*1g/cm0! a "*# &our (ring time would be ade=uate to meet re=uirements* A longer

time ma)es more sense! t&oug&! as t&e modulus of t&e ceramic increases notably

beyond "*# &ours* %&e cur+e begins to >atten out as time increases and s&ows less

t&an a 23 increase in density after roug&ly "*0 &ours sintering time* %&us! going

past "*0 &ours in an industrial setting would simply be wasting time and money*

Additionally! gi+en t&at t&e &eat up and cool down cycles ta)e roug&ly &ours!

adding anot&er #2 minutes to t&e process is a minor increase in processing time*

Gi+en t&e 2"3 increase in elastic modulus and t&us safety factor t&is increasewould bring for a 03 increase in manufacturing time! a sintering time of at least "*0

&ours is t&e best c&oice* It s&ould be noted t&at "*0 &ours was not a tested

sintering time! so it is possible t&at sintering for "*0 &ours would not yield t&e

e'pected results* %&us! to con(dently proceed wit& a "*0 &our sintering time! it

would be wise to test t&is sintering time in a lab*

:esigning a die to use in t&e pressing of t&e alumina powder for t&is

application re=uires anot&er c&oice to be made* Ene option is a die "* cm ' "* cm

' $*$ cm wit& t&e pressing direction being parallel to t&e $*$ cm a'is* %&e ot&er is a

die "* cm ' "* cm ' $*$ cm wit& t&e pressing direction perpendicular to t&e $*$

cm a'is* %&e (rst option &as t&e ad+antage of being simpler! re=uiring a smaller

press &ead and less consideration of e+enly distributing t&e load! but would &a+e a

muc& &ig&er /: ratio! li)ely leading to lower green and (red densities* A &ig&er

/: ratio leads to lower green density because a greater die &eig&t contributes

more wall friction! w&ic& opposes t&e compressi+e force! reducing t&e e?ecti+e

compressi+e force* %&e second option would &a+e a muc& lower /: ratio and

would li)ely lead to &ig&er green and (red densities! but would be more complicated

to create and use! as (lling! pressing &ead size! and e+en load distribution would all

be potential issues* :espite t&ese potential problems! t&e recommended die s&ape

is t&e second option! wit& t&e pressing direction perpendicular to t&e $*$ cm a'is*

%&is is because all of t&e e'perimental data from t&is e'ercise was gat&ered using a

die wit& a similarly low /: ratio* Switc&ing to a die wit& a +alue /: O #" would

Mueller #1


17/25

really re=uire a new e'periment to be conducted to con(rm t&at ade=uate (red

densities could be ac&ie+ed and would in+alidate most of t&e wor) done up to t&is

point* @sing t&e die wit& t&e pressing direction perpendicular to t&e $*$ cm a'is

gi+es an e'tremely &ig& li)eli&ood of being able to produce solid alumina wit& t&e

re=uired density and t&us strengt& for t&is application* %&e (nal consideration for designing t&is beam is to ta)e into account t&e

s&rin)age of t&e beam during (ring* @sing "*0 &ours as t&e sintering time and

e'trapolating t&e linear s&rin)age +alues found e'perimentally! it seems reasonable

to use #$3 s&rin)age in all directions* %&e desired (nal dimensions must be

modi(ed to ta)e t&ese s&rin)ages into account! gi+ing!

Mold Dimension=¿ Design Dimension

1−Shrinkage * ;<

It is considerably easier to mac&ine o? a small amount of material t&an add

material to a sintered ceramic! so it was decided to round up on mold dimensions*

@sing 8=uation and t&e s&rin)ages determined for a "*0 &our sintering time! it is

found t&at t&e mold dimension s&ould be roug&ly #*2 times t&e design dimension

for eac& measurement* Multiplying t&e design dimensions of "* cm ' "* cm ' $*$

cm by a factor of #*2 gi+es (nal mold interior dimensions of "*7 cm ' "*7 cm ' 1*1

cm* %&e die! pressing down perpendicular to t&e 1*1 cm a'is s&ould &a+e

dimensions of roug&ly "* cm ' 1*$ cm! to allow t&e die to mo+e t&roug& t&e

mold wit&out binding*

%o replicate t&e conditions used during t&is e'periment! a sintering time of

"*0 &ours and a sintering temperature of #"",- s&ould be used! as noted in t&e

e'perimental procedure* Gi+en t&e mold dimensions and a desired green density of

2*2$ g/cm0 to replicate t&is e'periment! eac& mold s&ould be (lled wit& 0*2 g of

alumina powder* Also gi+en t&e die dimensions and t&e " MPa desired stress

applied to t&e powder! again to replicate t&is e'periment! t&e load t&at s&ould be

applied to t&e die is 22!#1 or !7$ pounds of force* @sing t&ese speci(cations

and t&e process outlined in t&e e'perimental procedure s&ould produce materially

consistent samples t&at meet t&e design needs of t&e Alumina -orporation of

Minnesota*

Mueller #


18/25

9ecommendations

Ene issue t&at was noted during t&e e'ecution of t&is e'periment was t&at

simply using paper to load t&e powder into t&e die is not a +ery precise and clean

met&od* %&is leads to materials waste! inaccurate measurements! and most

importantly! die wear as spilled powder causes abrasion of t&e die* It would ma)e

sense to create or purc&ase a funnel4type tool to direct t&e powder directly to t&e

bottom of t&e die wit&out spilling or coating t&e inside walls of t&e die* %o best

replicate t&e successful results of t&is e'periment! it is recommended to use a die

wit& t&e pressing direction perpendicular to t&e long a'is of t&e beam! as t&is

reduces t&e /: ratio and &elps wit& pac)ing* As t&e current procedure gi+es a

green density of 2*2$ g/cm0! at or abo+e t&e typical range for alumina powders! t&e

current procedure or one similar to it s&ould be used in t&e creation of t&e beam*

As was noted in t&e design! t&e most logical sintering time to use would be "*0

&ours at t&e sintering temperature! as t&is time reduces t&e ris) of grain growt& and

coarsening w&ile gi+ing most of t&e possible density increase* %&is sintering time

s&ould (rst be tested in a lab to +erify t&at it yields t&e e'pected results before

mo+ing to production* Enly one sintering temperature was tested! #"",-! and it

ga+e a resulting solid wit& more t&an ade=uate propertiesC as suc&! t&is

temperature can be left unc&anged* %&is process gi+es a (nal solid wit& a density

of roug&ly 0*10 g/cm0 or "*$3 of t&e t&eoretical +alue for Al2E0 and an elastic

modulus of 27*0 GPa! w&ic& is well o+er t&e re=uired elastic modulus of 20*$ GPa

re=uired to build t&e beam* Finally! it must be noted t&at t&e beam will s&rin) upon

sintering as t&e material densi(es* %&is re=uires t&e die for t&e beam to be built

larger t&an t&e (nal beam to allow for t&is s&rin)age* %&e dimension increase factor

was determined to be #*2! gi+ing die dimensions of "*7 cm ' "*7 cm ' 1*1 cm* If

t&e user wants to truly eliminate t&e c&ance of a beam being undersized! a

dimension increase factor of #*2 or e+en &ig&er could be used* %&e data collected

in t&is e'periment s&ows t&at t&is process produces a material t&at meets t&e

product speci(cations and is consistent enoug& to Dustify mo+ing forward* %&e ne't

step s&ould be to create a die and mold in t&e speci(ed size and test t&e same

parameters ;green density! (red density< to pro+e consistency and create

speci(cations for scale4up to an industrial4scale process*

Mueller #7


19/25

Wor)s -ited

6odiJo+K! atarinaC Pac&! Ladisla+C o+Kr! ladimirC QerRans)y! AloDz* ;2""1

Alumina -eramics Prepared by Pressure Filtration of Alumina Powder

:ispersed in 6oe&mite Sol* -zec& Silicate Society! &ttp//www*ceramics4

sili)aty*cz/2""1/pdf/2""1T"T20*pdf

-ompaction of -eramic Powders* ;2"#$

&ttp//en*wi)ipedia*org/wi)i/-ompactionTofTceramicTpowders

Francis! Lorraine* ;2"#$< Sintering Lab andout! :epartment of Materials Science

and 8ngineering! @ni+ersity of Minnesota4%win -ities

Francis! Lorraine* ;2"#$< -&apter $! Powder Processes! @nnamed Materials

Processing %e'tboo)

Gupta! SuroDitC Green! :a+idC Messing! Gary* ;2"#"

-eramic Green 6odies :uring Presintering* Uournal of t&e American -eramic

Society! 0 21##421#1* :oi #"*####/D*#$$#42#1*2"#"*"07"*'

Sc&oenberg! S* 8*! Green! :* U* and Messing! G* L* ;2""1

t&e %&ermomec&anical Properties of a -eramic :uring Sintering* Uournal of

t&e American -eramic Society! 7 27V2$2* doi #"*####/D*#$$#4

2#1*2""1*"#"*'

Scott! G* :*C ilgour! :* M*C ;#1

6ritis& Uournal of Applied P&ysics! Series 2! olume 2*

ftp//ftp*esc*cam*ac*u)/pub/gcs2/6ac)upT2TT"7/P&:/-S:/Scott32"

32"ilgour32"#1*pdf

Sintering* ;2"#$

&ttp//en*wi)ipedia*org/wi)i/SinteringXAd+antages*

Mueller #


20/25

Sun! Yi4&ua! Ziong! Wei4&ao! and Li! -&en4&ui* ;2""

density [nE4Al2E0 ceramic composites by slip casting* %ransactions of

onferrous Metals Society of -&ina! 2";2"#"< 12410#

Aluminium E'ide* ;2"#$

&ttp//en*wi)ipedia*org/wi)i/AluminiumTo'ideXAbrasi+e

MS Precision 6alances*

&ttp//us*mt*com/us/en/&ome/products/LaboratoryTWeig&ingTSolutions/Precisi

onT6alances/MSTPrecisionT6alances*&tml# V :igital Precision -alipers

&ttp//www*generaltools*com/#44:igital4Fractional4-alipersTpT100*&tml

Mueller 2"

http://us.mt.com/us/en/home/products/Laboratory_Weighing_Solutions/Precision_Balances/MS_Precision_Balances.htmlhttp://us.mt.com/us/en/home/products/Laboratory_Weighing_Solutions/Precision_Balances/MS_Precision_Balances.htmlhttp://us.mt.com/us/en/home/products/Laboratory_Weighing_Solutions/Precision_Balances/MS_Precision_Balances.htmlhttp://us.mt.com/us/en/home/products/Laboratory_Weighing_Solutions/Precision_Balances/MS_Precision_Balances.html


21/25

Appendi' A :iscussion of :ata Analysis Met&ods

%o determine t&e reproducibility of t&e results! a $3 con(dence inter+al for

eac& +alue was calculated* %&e met&od used to determine t&e standard de+iation

was t&e standard de+iation function ;stde+*s< in Microsoft 8'cel* %&is +alue was

multiplied by t&e student t4test +alue for #$ or 0 degrees of freedom! depending on&ow many measurements were ta)en ;#1 or


22/25

Appendi' 6 8'perimental :ata

Thickness (mm< Diameter

(mm<

Mass (g< Green

Densit(g!cm3)

"e##et

$

1 2 3 4 5 me

an

"%&'

er

"e##e

t# #*7

##*7 #*7

0#*70

#*7

#*72 #2*# "*$$# "*$0# 2*2

2 #*71

#*7$

#*7

#*7

#*71

#*7$ #2* "*$$0 "*$00 2*21"

0 #*70

#*72

#*7

#*72

#*7

#*7 #2*$ "*$$ "*$2 2*20$

#*7

#*7

#*7

$

#*7

1

#*7

1

#*71 #2*1 "*$$2 "*$2 2*2$

$ #*7$

#*70

#*71

#*7#

#*72

#*70 #2* "*$ "*$2$ 2*21

1 #*72

#*7#

#*7#

#*7 #*7 #*7# #2*0 "*$$" "*$2# 2*21

#*70

#*7#

#*72

#*7

#*72

#*72 #2* "*$$" "*$21 2*212

7 #*71

#*70

#*7 #*7 #*71

#*70 #2* "*$$2 "*$2 2*201

:ouble

0*

0*17

0*1$

0* 0*0

0*" #2*7 #*" #*"12 2*20#

# #*7

#*7

1

#*7

0

#*7

2

#*7 #*70 #2*1 "*$$0 "*$2# 2*221

2 #*77

#*7

#*77

#*7

#*77

#*7 #2* "*$$1 "*$$" 2*27

0 #*7

#*71

#*71

#*77

#*7

#*7 #2*7 "*$$" "*$# 2*2$7

#*7$

#*72

#*7$

#*7

#*7

#*7$ #2* "*$$" "*$00 2*2

$ #*7 #*7 #*7 #*7 #*7 #*70 #2* "*$$# "*$0 2*271

Mueller 22


23/25

0 0 0 1 #*

#*70

#*7

#*71

#*7

#*7 #2* "*$$# "*$0" 2*2

#*7

#*70

#*7$

#*7

#*77

#*7 #2*72 "*$$# "*$0" 2*#7

7 #*$ #* #* #*# #*1 #*# #2*7 "*$ "*" 2*20A+erage

alue#*70 #2*$ "*$$# "*$27 2*2$2

Standard:e+iation

"*" "*"001 "*""2 "*"#0 "*"2$

@pper6ound

#*# #2*70# "*$$$ "*$$$ 2*0"$

Lower6ound

#*$ #2*177 "*$ "*$"# 2*#

%emp;,-<

%ime;&rs<

Fired %&ic)ness ;mm<

"e##et

$

# 2 0 $ mean

# #"" " #*10 #*$7 #*$ #*$ #*1# #*1"2 #"" " #*1# #*12 #*1 #*1# #*1# #*1#0 #"" " #*$ #*1 #*$7 #*$ #*$1 #*$7 #"" " #*$ #*1# #*1 #*1 #*$ #*1"

$ #"" "*# #*$2 #*$0 #*$2 #*$2 #*$$ #*$01 #"" "*# #*$0 #*$ #*$ #*$ #*$$ #*$ #"" "*# #*$ #*$1 #*$$ #*$ #*$ #*$$7 #"" "*# #*$0 #*$0 #*$ #*$ #*$ #*$

:ouble

#"" "*# 0*"$ 0*"1 0*"1 0*"1 0*" 0*"1

# #"" "*1 #*$# #*$2 #*$ #*$# #*$# #*$2

Mueller 20


24/25

2 #"" "*1 #*1# #*1$ #*$ #*1$ #*$ #*120 #"" "*1 #*$7 #*$7 #*$7 #*$ #*1 #*$7 #"" "*1 #*$1 #*$ #*$ #*$$ #*$1 #*$1$ #"" #*2 #*$1 #*$$ #*$$ #*$ #*$$ #*$$1 #"" #*2 #*$ #*$1 #*$2 #*$1 #*$0 #*$

#"" #*2 #*$ #*$1 #*$ #*$1 #*$1 #*$17 #"" #*2 #*1 #* #*$ #*1 #* #*$

Fired :iameter ;mm< Fired Mass;g<

Mass Loss;g<

density;g/cm0<

"e##et

$

# 2 0 $ mean

# ##*#"

##*#0

##*#2

##*##

##*#

##*#2

"*$#$ "*"#1 0*020

2 ##*#

##*#1

##*#$

##*#$

##*#1

##*#1

"*$# "*"#1 0*272

0 ##*#

##*#0

##*#$

##*#1

##*#

##*#$

"*$" "*"#$ 0*0"7

##*#0

##*#$

##*#$

##*#7

##*#1

##*#$

"*$# "*"#$ 0*22

$ #"*77

#"*77

#"*77

#"*7

#"*"

#"*77

"*$## "*"# 0*$1

1 #"*#

#"*0

#"*"

#"*"

#"*#

#"*#

"*$"1 "*"#$ 0*$#$

Mueller 2


25/25

#"*

#"*"

#"*7

#"*"

#"*0

#"*#

"*$## "*"#$ 0*$2#

7 #"*"

#"*7

#"*7

#"*"

#"*"

#"*"

"*$#" "*"# 0*$1#

:oubl

e

#"*

"

#"*

"

#"*1

#"*1

#"*1

$

#"*1

7

#*"0# "*"0# 0*1"

# #"*#

#"*2

#"*

#"*1

#"*

#"*

"*$"1 "*"#$ 0*1

2 #"*1

#"*"

#"*2

#"*2

#"*

#"*#

"*$0 "*"#1 0*11#

0 #"*"

#"*"

#"*#

#"*$

#"*

#"*0

"*$2$ "*"#1 0*1"

#"*"

#"*#

#"*#

#"*2

#"*2

#"*#

"*$# "*"#1 0*17

$ #"*1

#"*11

#"*1

#"*1

#"*#

#"*17

"*$2# "*"#1 0*$2

1 #"*1

$

#"*1

#"*

#

#"*

2

#"*

0

#"*

"

"*$#$ "*"#$ 0*#

#"*11

#"*1

#"*17

#"*$

#"*$

#"*"

"*$#$ "*"#$ 0*11#

7 #"*1

#"*1

#"*17

#"*17

#"*17

#"*1

"* "*"#1 0*1$1

A+eragealue

"*$#0 "*"#$ 0*$$$

Standard:e+iation

"*"#2 "*""# "*#1$

@pper 6ound "*$0 "*"# 0*"1Lower 6ound "*71 "*"# 0*2"

M ll 2$

Documents

Peter Mueller Sintering Lab Report