dticgrowindifferentshapes.tibisliabletogrowalong[010]directionandformshort-fibreshapeduetoit’sb27crystalstructure.theshapeoftibatcrosectionispolygon,thecrystalfacesarecomposedwith(100),(101)and(10).moreover,thereisstackingfaultintibandthestackingfaultislikelytoformat(100)crystalface.ticwithnaclcrystalstructuregrowsindendritic,equiaxedornear-equiaxedshape.
4.theeffectsofaluminumadditiononmicrostructureandmechanicalpropertiesofinsitusynthesizedtitaniummatrixcompositeshavebeeninvestigated.theadditionofalloyingelementaluminumdoe’tchangephasesandadjustthesolidificationpath.however,thealloyingelementhindersthenucleationandgrowthofreinforcementsthatresultinmorefinetibandticreinforcementsandmaketicreinforcementsgrowwithequiaxedparticleseasily.aluminumnotonlystrengthethematrixalloybysolidsolutionstrengthening,butalsoimprovesthemechanicalpropertiesbyrefiningthereinforcements.
5.theinterfacialmicrostructuresofinsitusynthesizedtibwhiskerandticparticlesreinforcedtitaniummatrixcompositeshavebeenoervedbymeaoftramiionelectronicmicroscopyandhigh-resolutiontramiionelectronicmicroscopy.theresultsshowthattheinterfacesareveryclean.theyarebondedwell.thereisnocoistentcrystallographicrelatiohipbetweenticandtitanium.however,therearefollowingcoistentcrystallographicrelatiohibetweentibandtitanium:,,(0002)ti//(001)tib,and,,(0002)ti//(200)tib.moreover,itiscloselyrelatedtothecrystalstructuresofreinforcementandmatrixalloy.theformationofabovecrystallographicrelatiohiisvaluabletodecreasetheenergyoflatt

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