摘要
60%whitecorundumusedforaggregate,5%aluminiumpowderforfixedadditionsand35%variousadditivesformatrixwerepreparedforspecimens1#,2#,3#.Theyweremixeduniformlywiththesuitableresinasabinderandpressedunderpressureof315tonforgingpress,thendriedat200℃for24h.Effectsofvariousadditiveson1500℃×2hcreeppropertiesofAl3CONreinforcedcorundumcompositewereresearched.Theexperimenalresultsshowthatcreepcoeffi-cientsofspecimens1#,2#,3#at1500℃×2hare1.4×10-4,-9.4×10-4,-22.6×10-4,respectively.CrushingstrengthoftheslideplateaddedwithsuitableadditiveAafterfiredat1500℃×3hreachesto225MPa,thecreeprateispositiveallthetimefrom0%to0.014%at1500℃for2h.Themicro-structureresultanalysisshowsthatreinforcedphasesofAl3CONfibercompositehavebeenformedafterfiredwithAlpowderincokeathightemperaturesforspecimen1#,andthestrengthofthecompositeisincreased.Thehotmodulusofruptureisupto59MPaat1400℃andtheRULisobvi-ouslyhigherthanthatat1700℃.ItsservicelifeistwotimesasthatofAl2O3?Cslideplatewhenusedintheprocessofpouringsteel.Themechanismofcreeprateresistanceofthecompositescanbedis-coveredbymeansofSEMandEDAXanalysis.ItisconcludedthattheactiveAl3CONandAl2O3multiphasesthatwereformedbyN2ingas,C,AlandAl2O3insidethematrixofthecompositesduringin-situreaction,whichgivesthecompositesoutstandingcreeprateresistanceforthedensezonere-sultingfromAl3CONoxidationthatinhibitscontractionatthehightemperature.Besides,thematrixwillturnintothemultiphasewithhighrefractoriness,NcontentanditsAl3CONreinforcedfiberwillfurtherincreaseaccordingly.Inaddition,Al3CONformedbyAl2O3andC,AlinthematrixwithN2ingaswillinhibitthecreeprateandalsogreatlyimprovethecreeprateresistanceofthecomposites.
出版日期
2008年06月16日(中国期刊网平台首次上网日期,不代表论文的发表时间)