DISLOCATION PINNING IN HIGH TEMPERATURE DEFORMED Ni_3(Al,Ti) SINGLE CRYSTALS CONTAINING DISORDERED γ PRECIPITATES  

作　　者：W.H. Tian M. Nemoto 

机构地区：[1]Department of Materials Physics and Ghemistry, University of Science and Technology Beijing, Beijing 100083, China [2]Sasebo National Gollege of Technology, Okishin 1-1, Sasebo 857-1193, Japan

出　　处：《Acta Metallurgica Sinica(English Letters)》2006年第3期157-164,共8页金属学报（英文版）

基　　金：the Grant-in-Aid for Scientific Research from the Ministry of Education, Science and Culture of Japan ; the National Natural Science Foundation of China （No. 59971008）.

摘　　要：A transmission electron microscopy （TEM） investigation has been performed on the dislocation pinning in Lie-ordered Ni3（Al, Ti） containing disordered γ precipitates.The morphology of deformation induced dislocations in the γ base alloys containing fine dispersion of disordered γ was investigated by means of weak-beam electron microscopy. The superdislocations are strongly attracted to the disordered particles and dissociate on the （111） plane in the γ particles, while they dissociate on the （010） plane in the γ＇ matrix. The disordered γ precipitates play an important role as a pinning point during the cross-slip of superdislocations from （111） to （010） planes in the γ matrix and restrain the cross-slip of superdislocations. The interaction of superdislocations with disordered particles causes the formation of superkinks, jogs and closed loops.A transmission electron microscopy （TEM） investigation has been performed on the dislocation pinning in Lie-ordered Ni3（Al, Ti） containing disordered γ precipitates.The morphology of deformation induced dislocations in the γ base alloys containing fine dispersion of disordered γ was investigated by means of weak-beam electron microscopy. The superdislocations are strongly attracted to the disordered particles and dissociate on the （111） plane in the γ particles, while they dissociate on the （010） plane in the γ＇ matrix. The disordered γ precipitates play an important role as a pinning point during the cross-slip of superdislocations from （111） to （010） planes in the γ matrix and restrain the cross-slip of superdislocations. The interaction of superdislocations with disordered particles causes the formation of superkinks, jogs and closed loops.

关 键 词：superdislocation PRECIPITATE attractive interaction cross slip Ll2-ordered Ni3Al 

分 类 号：TG111[金属学及工艺—物理冶金] TG146.15[金属学及工艺—金属学]