全层片状TiAl 基合金断裂过程的原位观察.PDF

* T iAl TiAl * - In Situ Observation of Fracture Process for TiAl base Alloy with Fully Lamellar Microstructure ( ) ao Peng He Yuehui Huang Baiyun Liu Wensheng ( entral South University of T echnology) [ ] SEM , Ti-33Al-3 r -0. 5Mo ( wt % ) , T iAl , ; , , TiAl , TiAl / 2 TiAl [ Abstract ] In situ observation of the tensile fracture process for Ti-33Al-3 r-0. 5Mo ( wt %) alloy with fully microstructure was conducted in this work Fully lamellar TiAl alloy ex-. hibits high fracture toughness. The crack bifurcation results in crack-tip blunting during tensile process T he formation of shear ligaments by mismatched crack planes might lead to an enhance-. ment in the fracture toughness. T he fractograghic analyses show that the translamellar fracture and cleavage of interfaces are the two dominant fracture modes. Keywords T iAl-base alloysfracture toughnessfracturein situ observation 1 3 r-0 . 5M o) 1050 , 48h - Ti Al 1250 , 170 , 2 MPa h HIP [ 6] , [1] , 35mm 7mm 1mm ( ) 3 0. 4 , SEN