简介:TiN-Al2O3compositepowderswithdifferentTiNcontents(0,10vol%,20vol%,30vol%and40vol%)werepreparedwithmicrometerTiNandα-Al2O3powder(theirpuritieswere99%)asstartingmaterialsbywetballmillingfor5h.TiN-Al2O3compositewerethenpreparedbypressingtheabovecompositepowders,dryingat200℃for12handfiringat1800℃for3hinnitrogenatmosphereinhot-pressingfurnace.TheinfluencesofTiNcontentonmechanicalpropertiesandelectricalconductivityofTiN-Al2O3compositeswerestudied.TheresultsshowedthatthemechanicalpropertiesofthecompositeincreasedwithTiNcontentincreasing,whiletheresistivityofcompositesdecreased.Acompositewith40%TiNhad498MPabendingstrength,4.285MPa·m1/2fracturetoughness,1.34×10-3Ω·cmresistivity.TheSEManalysisshowedthatthefineTiNcrystalsdistributedamongthecrystalboundaryofAl2O3matrix.Theybondedtogetherforminganet-likestructurewhichplayedaroleofrestrainingAl2O3grainsfromgrowingup,tougheningandstrengthening,sothemechanicalpropertiesofTiN-Al2O3compositewereenhanced.