ngthereactionbetweentitaniumandb4c.however,coideringfromchemicalbalance,tib2cannotexistintitaniummatrixalloystably.theabovereactioreleasequitealotofheat.moreover,theadiabatictemperatureisgreaterthanthetheoreticalcriterion,whichindicatesthatthereactioncanbesustainedbyitself,namelyself-propagationhigh-temperaturesynthesisreactioncanoccur.
2.titaniummatrixcompositesreinforcedwithtibwhisker,ticparticleortibwhiskerandticparticlehavebeenproducedbynon-coumablevacuumarcremeltingfurnaceandcoumablevacuumarcremeltingfurnace.theresultsofx-raydiffractionshowthattheinsitusynthesizedreinforcementsaretibandtic.thereinforcementsweredistributeduniformlyinmatrixalloy.theshapesofreinforcementsareshort-fibreshape,dendriticshapeandequiaxedshapeornear-equiaxedshape.thereinforcementwithshort-fibreshapeistib,thereinforcementwithdendriticshapeandequiaxedshapeornear-equiaxedshapeistic.theexperimentalresultisingoodagreementwiththeoreticalresult,whichprovidesgistforcommercialproductionofinsitusynthesizedtitaniummatrixcomposites.
3.thegrowthmechanismsofreinforcementsininsitusynthesizedtitaniummatrixcompositeshavebeeninvestigated.thegrowthmecha
nismsarecloselyrelatedtosolidificationpathsandcrystalstructures.thereinforcementsdiersefrommeltandgrowinthewayofnucleationandgrowth.fortheinsitusynthesizedtibwhiskerandticparticlereinforcedtitaniummatrixcomposites,thereinforcementsundertakethefollowingthreestages:primarycrystal,binaryeutecticandternaryeutectic.duetothedifferentcrystalstructures,tiban
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