【摘要】 在ＳＥＭ和ＴＥＭ下对Ｔｉ３３Ａｌ３Ｃｒ０．５Ｍｏ合金全层片组织薄板状和薄膜状试样分别进行了动态拉伸，并原位观察了试样中裂纹的形核及扩展过程．发现裂纹遇到内相界面时会发生偏转或裂尖发生钝化；主裂纹主要以使剪切带断裂而与微裂纹相连接的方式扩展并沿曲折路径进行．更多还原

【Abstract】 The in situ tensile of a fully lamellar TiAl alloy, with a composition of Ti 33Al 3Cr 0 5 Mo(mass fraction %), was performed with plate and foil specimens in SEM and TEM respectively. The process of initiation and extension of crack was in situ observed. The results revealed that the crack would deflect and its tip would blunt when it met the interface; the extension of the main crack was performed by the shear ligments fracture to connect with microcrack; the extension of crack had the tortuous path.更多还原