THERMAL ACTIVATION ANALYSIS ON TENSILE DEFORMATION IN Ti47Al2Mn2Nb ALLOY

作     者：Yu Wang 1) , Dongliang Lin (T. L. Lin) 1) and Chi C.Law 2) 1) School of Materials Science and Engineering, Shanghai Jiao Tong University, Open Laboratory of Education Ministry of China for High Temperature Materials and Tests, Shanghai 

出 版 物：《中国有色金属学会会刊：英文版》 (Transactions of Nonferrous Metals Society of China)

年 卷 期：1999年第9卷第S1期

页      面：290-297页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

主　　题：intermetallics titanium aluminide TiAl alloy thermal activation tensile deformation dislocation motion mechanism mechanical properties 

摘      要：Activation volume V , activation enthalpy Δ H , activation free enthalpy Δ G and activation entropy Δ S of tensile deformation of Ti 47Al 2Mn 2Nb alloy with near lamellar microstructure were measured at yield point using strain rate jumping method in a temperature range from 77 K to 1 373 K. Based on the measured values of activation parameters and temperature dependence of tensile properties, different thermally activated dislocation motion mechanisms were speculated to control tensile deformation of the alloy in three temperature regions: in low temperature region (77～398 K), the mechanism is mainly characterized by the overcoming of Peierls Nabarro friction; in intermediate temperature region (398～1 073 K), the mechanism is an abnormally weak thermal activated motion; in high temperature region (1 073～1 373 K), dislocation climbing is the controlling mechanism.