Note: Descriptions are shown in the official language in which they were submitted.
2Q2~64~
1875/05885-A CG/SD ~ I
:
CBRA~UC ~ CO~IPOU~D C~ F~o ~~7
¦ Th~ ~pplloat~on cl~ime the priority under 35 U~ S119
of We~t G~rma~ Appliaation 8er. No. P.3924268.4 filed July 22,
198 9. ~ho ~ntire content~ ~f th~ priorlty document ~re
lnc orpor~t~d by reference herein. ~ :~
E~E ~D OF INvE~ - ~1
~he i~ nvention rela~e~ to ~ cer~mic ~etal compound
(C~ C~, con~i~t ing of ~ pero~ o~ramic ~nfiltrAted with mot~
BaS E~GR~) ~ OF ' r~ TN~NTION C~ B ~/I~o 35/6~ ~$
~he ~u rope~n Pstent 0 155 831 ~L~nx~d0) publl~hed on
Sep~em~or 25, 1986 dio~lo~e~ eramlc mot~l mate~ial compo~ed
o~ ~ thre~-dlml ~n~lon~l ~ntoraonnected polyary~talline ~truc~ure
con~sln~ng 2-' 1~ ~volume lbasi~) of ~ metall~c oon~tltuent.
~cc~ding to cla~m 11 of tho ~anxide patent, the ~mall Angle ::
~rain boundar1e~ of the aer-~Lc body ~u~t lie within certa~n
ran, ae~, ~0 ~hlt good in~iltratlon of the oerRmlc body b~come~ -
po~ 3ible.
~he J ~p~nese paten~ 61/16322~ (Sun~Lto~o Electric .
: Indl ~tries) pu bli~hed July 23~ 19~6 discloses the infilt~tion
o ~ cerumic body havlng ~ porosity of 85 - 90~ with an 1- ::
alu~inum melt I lnder pre~ur~.
~F y~ M~roov~ ~r, the ~riti~h Pat~nt 21 48 2~0 ~B~lt~h ~o~
30~ R 8~ ~arah AB~OC iatlon) publl~hed May 30, 1985, di~clo~e~ the~t : ~
;~/Ioen net~ (which are a~tually defined in the art a~ products ~ :
en~ !rat~d by B. Lntering two dlfferen~ ~atori~le: ceramic.p~wder~
a~d metalli¢ powder~) oan be produced by infiltrHting n pOrOUB . .
8iLC oerAmic h ~ing a porosity of 39~ wi~h molten ~lum~Lnum ~t
700tC and a pr~ur~ of 6.72 kpsi. : ~.
¦ ~urthe~ c~rm~t~ re de~r~b~d ~ th~ Czechoslovak~an .~.
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202~6~5
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Pa~ent CS 20'61 32 of October l, 1~3. They a~e made by
evacuating a porous ~eramic material made of 90 - 95~ Al2O3,
tho r~malnder ~eln~ 8102~ and infiltr~ting it w~th alu~inum or
~lt ~mlnum comp~ ~u~d3 at temperatures of 700 - 900-~ under an
S ~nt ~rt gR~ and at a p~es~ure of m~re than 1 MPa. aefore the
ini lltr~tion, the molded ceramic article ha~ a porosity of 41%.
Th~ di~lo~ur~ ~ of the feregoin~ documents that pert~Lns to
tYE ~e~ of mato ~rial~ that can be u~ed for cermets or C~C'~
(d~ If~ned belo~ r) and to method~ o~ infiltr~tion ia incorpor~ted
~ reference.l
¦ It ti ~orefore Appeer~ that highly porou~ cer~mic
materiAls have I ~e~n ln$iltr~ted with ~ metal m~lt, ~o that the
prc du~t made t :herefrom ha~ pr~dominantly A ~etal}ic structure.
~hi 8 t~pe ~flcer~mic metAl compound (CMC~ rgely of 8
met allia natu re in itB pro~ertie~, ~o that lt~ hardnes3,
te~ erAtuxe re ~i~ta~ce and we~r ~ehavi~r lie far ~elow tho3e of
~trlctly cor~m lc mater~ls.
! CMC~ f ind a v~riety of u~e~, for ex~mple, in automoblle
And aexwpa4e applications ~uch a~ break d~sk~ va~ve seats,
clu tch p~rt~, bearlngs)5 and other qeneral eng1neering applica~
t~c n~ a~ is w~ known ln the art.
1! Cq!S OF q!~lE
It i~ ~n ob~oct of the pre~ent inven~ion to devi~e :; `~
CM~ '~ that ha~ re one or more of the follo~ing ~mproved proper- ~ -
tl~ e: bending 6trength, toughness~ m~dul~s of elasticity~
haI dne~ and ~ ear re~$~t~n~e (whlch ~re U~UA11y poor in cer~mic i .
mat erialB but ~re ~uperior in metallic materi~l~) whil~
ret aining or . mproving propertle~ ~uch ~ hardne~ beh~ior at :
ele vated t~mp~ ~tures and wear reffistance, in wh~Gh cer~mic
mat r~ ~1B are nornally ffuperlor to metallic ma~erial~. Anothor
ob; ~t ~ to devl~e methods for maklng CM~'~ having ~t leA~t
one of the fc regoing propertle~ and yet ~nother object i8 to
dev ise method~ for u~ing ~uch CMC'c.
S ~ Y OF ~F INV~N~ION :-
~ It hal ~ n ~scertA~ ned thAt, $f ~ multilQyer ~
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h~in~ more thAn three ~n~ preferably mere than S layers)
cer amic oon~t~ uction havlng ~n overall poro~ity of 5 - 30~, ~8
lnf iltrA~ed w Lth molt~n m~t~I the de~ir~d combln~tion of
px~ pertle~ car bQ achleved. The over~ll porosity, moreo~ex, 14
the initlal p Drosity o~ the ceramic be~ore infiltrAtion wlth
~ol ton metal. Of grea~ lmportance ln thl~ aonnection is the
AVe r~ge pore ~diu~ of a~out 100 - to about 1,000 nm, of the
ini ti~l cer ~ c ~efore ~nfiltr~tlon whlch ia deter~lned with
th~ halp of A ~arlo-Erba mercury poro~lmeter (Model 2000)~
By ~e~n~ of the multllAyer str~ctur~, a pore network
~txucture of t~e c~r~mlo mAterial i8 attained, whioh can be in-
~i~tr~ted in ~ pa~tloul~rly ~dvan~ageou~ manner with a molten
met al. Pursul Int to the lnven~ion, th~ poxe network structure
c~n ; be aontrol led by the p~rtlcle Blze of the materlal uset to
mak e the cer, ~la body ~ well ~8 by the r~te of ceramlc
dep o~ltlon u~. .ng preferably A liquld-st~bili2ed plasma jet to
fo m the c~ra~ lc body.
It hA~ I now been ascertained by means of experiment~
th~ t the ~m~l 1 Angle ~rain boundar$~ g~ven in tho L~nxi~¢
pat nt, are not nea-~sary, lf the cer~mic has * pore netwo~k
stl uctur~, which iB built up ~rom pores and por~ chAnnel~,
wh~ oh ~re aonnected to one another. Pursu~nt to ~ho invention,
thi ~ 8pecial ~tructure i~ o~tained if the aeramic is bullt up
by pl~m~ ~prlylng, whioh re~ult~ in the 4uccessive depo~ltion
25 of ssver~l th~n layer~ of ceramic on A rotat~ng mandrol. The
thickno~ o~ ~ ~aoh pl~sma~spray~d layer can be adju~ted to hs~e
a l ~e~ired val ue w~thln the re,nge of ~ ~o~t 5 and ~bout 120
mic rons. All type~ of rot~t$on~11y ~ymmetricAl shape~ cAn thu6
be produceds ~ ~.5., coneo, cylinde~ and t~ w~ 8 more
30 Col~ ,pl-x ~h~pe~ .
Furthe r detail~ on the ~Anufacture of th~ in~t~nt
cor ~mic~ Are p rovlded below~
Fox ce rtain applla~tlon4, ouch 88 the ~oining to ~et~l
~tr uctures Ruch ~ welded or soldered cer~mt~J~tal const~uc-
~5 tic ns, lt h~slproven ~o be useful to h~ve th~ poro~ity o~ the
I .
202~645 ~ ~
: 1 4
cer ~1~ m~ter~ ~l increass from the lnside to ~h~ ou~lde ~nd
thu 5 to have an lncrea~lng p~oportion of metal towards the
out ~lde. A po re netwo~k of ~uch a con~truct~on i8 xeferred to
as ~ ~grad~ent ~tructure." ~h~ metallic propert~ pred~minate
ln the outex zl ~ne of the compo~nd, while the ~eramic propertie~
are preemln~nt ln the lnterior.
g radlent ~tructure 1~ achleved by a ~ari4tion ln
~be¦ part~cle ~ ize during the ~p~y~g onto thr~ ba~e ~ody in ~
liq ~id-~t~b~ zed plasma jet. Method~ fo~ making c~ramlc
~od Le~ ~y pla~ Im~ ~praylng are de~cribed e.g-, ~n ~-S- Paten~
No~ . 4,657,794 , 4,4~0,52g ~nd 4,547,415~ hrareby ~ncoxporated by
re~ ~ence in t~eir entiret~. S~ a7~o Schindl~r, 5. and
Sch ~ltzra, W., I~ oerum 37: 39-42, 1988 ln~orporated by
ref 3rence in lit~ ~ntlrety. For example, a hydro~en-oxygen
pla 3ma m~y be generated in a burner, rea~h~ng a high temp~ra~
tur a (~.~., 15 ,000C) at its center and ceramic powder i~ fed
~nt~ the pla-m~ ~ beam as the latter 1~ being dischar~ed from ~he
bur~er . ~he ~ot plA~mA meltR the ~u~f~c~ of ths powder and
d~pl ~lt~ lt ln that state ~nd ~t ~ high gpeed on the rotatlng
(t~ pically metsl) mandrel. On ~mpact, the p~rt~cle~ deform,
oon 3tituting a: I ~nte~conn~cted compound, and cool down qulckly
Suc~ :esqive pas, ~eB of the pla~m~ creA~e vArious l~yers.
For ac h$~1ng the gr~di~n~ ~tructur~, for example, a
ver ~ fine powdl ~r ~part~ ze range2 from about 5 to ~bout 50
mlc, con~ ~n di~ neter~ with ~ dso f 20 micron~ i8 inltlally u~ed
~ds~ m~y vary : Erom a~out 15 to ~bou~ 25 mlcrons). The partlcl~
~iz~ ln the o~ Iter layer~ of tho c~rhmic materiR~ ncr~ed
to l~ d50 v~l ~e of betwoon ~bout 75 ~nd About ~5 microns
~pr, ~fer~bly ab ~ut 80 mlcron~) wlth the r~nqe of part~cle ~ize~
vAr ylng betwee n about 40 and abo~t 120 ~icrono. ~o~Y~r~ t~e
r~v, ~r~e proced ure i~ ~180 pos~ible, dependlng on the sid~ of
th~ CNC thA~ ~ ~11 face the met~l surface upon u~e. ~t ~8
pre Eerred that¦ the ~urfaao of the ~or~mlc ¢ompound, which i~
clo ~e~ to th~ metal con~truction, ha~ ~he #tructur~ produc~d
fro~ n the powder wlth the l~rge particl~ di~m~ter, ~.e~ the
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20216i~
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t$ucture with the moi3t metal-like character.
A multicomponent maberial, based en at lea~ two oxide
~u~ta}~le for ~kin~ eramici~, e.g.:
Oxid~ ~1~ :
11 ~1203.1 ~! IgO : 2100C
1 A1203. 1 5 IiO~(other ratloi~i po4sible) lB60
3 A1203.2 S i2 : 1~20-~
1 ZrO2 .1 81 2 ~ 2500-C
Il ~1203. 1 MgO. lSii32 : 1471~C
1 al~o:
A1~03.ZrO2 i~t~b~l~zed with MgO, ~a~ or Y~03 with amount depend- .
ins on degre~ o~ ~t~bilization dei~ired, ai3 ~ B well known ln th~
Ar~
lS ca~ advantage~uisly be u~ed in the pre-reacted i3t~te, i.e., two
or ~ore fi~ode~i3 one for esch oxlde oomponent ~an ~e ulied in the
ple .Jm~ isipray, apparatu~i, the component~i belng fed ln
stc ichlo~etrlcl amount~ he compen~nti3 can then ~e rQacted ~n
~1~ U in the pilai~a beam emd d~po~ited on ~hi~ mandrel. Thu~
fo~ ~x~mple ~¦ 1s1 ratio of alum$n~ and tit~nlum dioxide can
for m alumin~ ~itanate in ~i~u and be depo~ited as such o~ the
m~r drel. ~o~ ver, pr~-r~A~ted Al-titanate c~n al~o ~e u~ed.
It ~an ~o ma~e by m~xing, mel~lng and gr~nd~ng alumlna and
tit~nium dioxi t~ and the rosulting particles ~an then be fed in
the pl~m~ ~pl ayer. The ~Qme i~ ~rue of other cerAmic~ within
the invention. ) I~ ~hould ~ under~tood that in pr$nclpl~ any
oer ~mic ox~de material~ can be u~ed, with dif ~e~ent one~ belng
pre rerre~ ~ep~: ~dlng on the end u~e of the ~M~ ~ iY apparent to
tho ~e o~ ortln, ~ry ~kill in tho a~t.
~ulticomponent m~teri~l~ are under~tood to be mixtures
of 2 or ~ore c~r~mic oxid~ m~ter~al~ which Are converted to
the powder f~ ~m by grinding hnd pre-reacted at ~lnterl~g
tQm per~tures, . i.e., gener~lly within th~ r~nse of nbout 1500 to
~bo lt 2500-C c !epending on the part~aular m~t~$al B~ i~ well
kno1 wn in the ~rt. There fter they ~re introducod lnto the
i
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1 re~ction zone of the pl~cma burn~r. - :
I ¦ The i~ l~entlon i8 furth~r de~cribed b~low in gre~t~
de~nil by ~ea ~ of Beveral non-limiting ex~mpleB of the lnven-
~ tl~ ~e ceramlc I let~l co~pounds being produced ~y pla~ma gprayin~
1 5 ~nc , then pXOCI ~Bad by infil~rAt~on with ~et~l ~nto ~MC. ~hey
~r~ I comp~red ~ ~lth eonvent1Onal C~C or cerm~t m~t~rlal~ includ-
inS mater~al~lproduced in acaord~nce with the ~anx~de Patent. -~
¦ By ~o dolng, lt 1~ ~een that ~h~ msteri~l propertl~o of the
¦ in~ ~onti~e CMC '~ have been d~tln¢tly improved, especlally ~ f! lo th~ Iy have the gradient struc!ture~ described above by which the
! lnd ,lv~dusl cer amic ~ay~r~ of the compou~d have different form
¦ fac tox~, most¦p~rticularly form factor~ that decre~se from th~
I inE ide to t~e outslde or, conver~ely, form factor~ that
¦ lnc rea~e from¦the lnside to the out~ide. Preferably~ the form
I 15 fac tor (i.~ the thickne~ss~urfhce r~tio) of ~ch l~yer i~
I gr~ !~ter than ~:S ~hether the ~ayors hav~ different for~ f~¢tor~
! or not.
¦ ¦ ~he de n~ity and poro~ity value~ h~e been determin~d by -
th~ method~ of DIN 51056 ~Augu~t 1985: Prufung kerami~cher Roh-
I ~0 un~ Werk~toff~ I; B~otlmmunq der WaQ~erau~nahme und der of~enen
I Poso~itat) and tho Vi~ker~ hardne~s value8 have been d~t~rmlned ~ :~
I bylthe me~od of DIN 50133 (Fe~ruary 1985: Prufun~ m~tRllisc~er
! We~ k~toffeS H~ lrtepruf~n~ nach Vickers; B~rolch HV 0,2 b~ Hv ~ I
! lol , Pub~i~he r~ ~euth Verl~g Gmb~ surggr~fen~x~ 6, 1000
Be~ lin 30, G~ ~rmany). To be~in with, panel~ o~ A12O3 and
Al ~iO5 mater~ al~ a~e produced ~y pla~a eprayinq in accordance
I wit h, e~ Sc :h~ndlelr, ~u~rs; ~ U.S. P~tent No. 4,6S~,794; or
I ~ de~cribed ~ Ibo~ he particle ~ize d50 wao betwe~n 60 and
~ 70 mloron~ ~n~ ~ the veloaity of the pla~ma jet wa~ 3~0 m~.
j 3d ~ht th~ckne~ of the 1nd~1d~al l~yero (whlch c~n be a~ many ~ :
nee Ided) appli ed wa~ 100 ~cron~ and the overall poro~ity
~c~ ,iQ~d w~ 18& for alum~nu~ oxld~ and 15~ for alu~lnum
t$t .anate. The ~ form factor of ~he pa~ticles ~prayed on wa~
to 1 s 20 for sluminum oxide and 1 s 15 to 1 ~ 25 for
35 A~ :minum titan at~.
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¦ ~e~t piece8 ~A ~t~ti8tiCAlly ~i~nifie~nt numb~r, su~has¦20-30) with the d~men~ions o~ 100 x 100 x 30 mm were cut
frdm the~e pA~els for dete~mining the charact~riatle mAter~l
v~l ue~, prsh~t~d to ~ tempera~ure o~ 1,0~CDC ~nd in~lltrated
w~t h a molt~nlmet~l Qonsi~ting of an ~lSiloMg allQy at 750~C
wit h ~ pr~ure difference of 3S bar within a period of up to
~bc ut ~ ~conc I~. The ~ooling rate af~e~ the infil~r~tlon waR
20C ~C per hou r in A progr~m-aontrolled furn~oe~ 80 that th~
pA~ t~ had coot~d down to room temperature w$thin 5 hour~. ~The
pr~ ferred pre~ ~eating temp~r~tu~e iBI for ~xample, with~n the
~n ge of abou t gOO-lOSO-C for aluminum And aluminum alloy~;
~bc ~t 1250-140 0-~ for aopp~ and copper alloy~; and ~out lOS0-
115 0OC for re~ and yellow brs~s. }n oth~r woxd4, it depend~ on
the ~etal. ~he po~t-inflltr~tion cooling rate i8 prefer~bly
~bo ut 1~0 to ~out 220-~ per hour. The infiltratlon pre30ure
i~ u-u~lly w~k~ln the range o~ AlPoUt 10-350 bA~, pxef~rably
~bo ut 30-4~ ~a~. Other in~iltration msthodo could ~lso be uged
C~8 r~fc~ t~ ove or I~B well-known in th~ art. )
After khat, the re~ldual pore volume w~s found to be 59~;
ofIthe lnlti~ ~1 poro~ity in the ~ of tho ~lu~ln~m oxtde
cer!amic ~nd 7! ~ ln the ca~e of ~lumLnum ti~Anate~ ~ho~e w~r~
aa~ording to the lnven~on ~ut without tha grad~ent feature.
I A fur~her experimental body wa~ produaed W~th tho
i ~ent~ve gradl~nt ~tructure. ~he m~nufacturlng condit~Qn~ ~re
th~ ~ame a~ tho~e a~ove; how~r, particle~ of two different
~i~e~ with ~ dso value of 40 ~n~ 100 micron~ re~pecti~ely ~ore
ap~lied throu~h two powder-feeding channblo ~nd fed lnto the
pl~ma beam. I~he feed rate of particlo~ w~th the dso value of
40 microns isIlncr~oed oontinuously from 0 to 25 kg/h, while
the feed rate ~f part~cles with the dso value o~ 100 ~cron~ i~
dec~e~d to tho ~me extent fro~ 25 k~/h to 0. Equal ~mount~
of eaoh mater~al w~re u4ed. The switchin~ ov~r from the one
fe~ ding chann~l to the other take~ pl~ca with~n onè hour in
thl ~ ex~mple hut ln gen~ral d~pend~ on the dimension~ of th~
35 ~er Amlc body ~IB well a~ on it~ w~l~ thicknes~. The thickn-s~e~
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f !the individual leyer~, ~o obtain~d, lie b~tween 8a and 100 -
mlqron~ and the overall porosity ~o 12%. ~ter in~iltratio~
wi~h an ~lSill ~Mg alloy, tho exparimsntal bod~ hAd A . residual
pore volume oi a.6~, b~ed on the initial poro~ty, ~nd a pore
ra9iu~ ranging fr~m about 200 to a~out 700 nm.
~4~ ,1Q :~
~he value~, j ~ea~ursd on ths experimental ~odies, are BU
m~ ~l~ed in T~ ~le 1. ~hQ value~ for the bending strength (~
po nt bendln device), modulu~ of elasticity ~nd fr~cture :
tol ghnes~ wer deterFined on European st~ndArd bendlng ~umples
ha~ ~ng the dil ~n~ion~ of 3.5 x 4.5 x 45 mm. T~e materlal data
(1 terature v lue~) of a conventionally prepaxed, ~ntirely
ce~ mic ~lnte ed body o~ A12O3 are glven for ~ompari~on ~cee :~
fi~ ~t column f ~able 1 wherein the sintered A1203 is fully :~:
lS del .~o: ~ore t an 99.5%). Al~o the Lanxlde p~en~ material w~
~ t~d ~ee l ~t column of ~able 1). All other column~ ~re
d~1 a from te~ lng of mater~als according to the invent~on. It
tu~ n~ o~t tha the metal-~eramic compounds, produced pur~ant
to the inv~nt on, have v~ry goot valu~s for bending ~t~en~th,
~0 fr cture toug n~ nd S~rdne~ and thu~ repre~ent a ¢l~ar .-
iml rovement i~ comparl~on with eonventlon~l materi~ls and th~
Lan xid~ ~iMC ~ terial with respect to the com~$nation of the
ch~ ~rac~ristic mat~r~Al value~ a~ well a~ with re4p~c~ t~ th~
va~u~ of th~lr i~t$v$du-l prop-rtio~-
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