To study the effect ofαphase morphology(equiaxedα(αE)/lamellarα(αL))on the in situ tensile behavior of TC21 alloy,the slip band,dislocation,crack initiation,and propagation were analyzed by scanning electron micr...To study the effect ofαphase morphology(equiaxedα(αE)/lamellarα(αL))on the in situ tensile behavior of TC21 alloy,the slip band,dislocation,crack initiation,and propagation were analyzed by scanning electron microscopy(SEM)with in situ tensile stage and transmission electron microscopy(TEM).The results show that the slip bands first concentrate in theαE phases and easily truncate at theα/βphase boundaries,whereas the slip bands move across theαlamellae in theαL phase.Microcracks are easily generated inαE orα/βphase boundaries with large plastic deformation.When the quantity ofαL is more thanαE,the crack tip is more easily deflected atαphases orαclusters with different orientations,making the main crack propagation path more zigzag.When the volume fraction ratio ofαE toαL is~3:4,i.e.,the volume fraction ofαE is close to that ofαL,TC21 alloy exhibits better strength and slower crack propagation rate.展开更多
基金financially supported by Guizhou Science and Technology Project(Nos.(2018)1027 and(2019)2165)the Engineering Research Center Project from Guizhou Provincial Education Department(No.(2017)016)。
文摘To study the effect ofαphase morphology(equiaxedα(αE)/lamellarα(αL))on the in situ tensile behavior of TC21 alloy,the slip band,dislocation,crack initiation,and propagation were analyzed by scanning electron microscopy(SEM)with in situ tensile stage and transmission electron microscopy(TEM).The results show that the slip bands first concentrate in theαE phases and easily truncate at theα/βphase boundaries,whereas the slip bands move across theαlamellae in theαL phase.Microcracks are easily generated inαE orα/βphase boundaries with large plastic deformation.When the quantity ofαL is more thanαE,the crack tip is more easily deflected atαphases orαclusters with different orientations,making the main crack propagation path more zigzag.When the volume fraction ratio ofαE toαL is~3:4,i.e.,the volume fraction ofαE is close to that ofαL,TC21 alloy exhibits better strength and slower crack propagation rate.