中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
Vol. 8 No. 3 September 1998 |
(The Education Ministry of China Open Research Lab for High Temperature Materials and Testing,ShanghaiJiao Tong University, Shanghai200030, P. R. China)
Abstract:Al67Mn8Ti25powder was produced by high-energy ball milling and then consolidated by vacuum hot pressing and hot isostatic pressing. The effects of mechanical milling on the structure and properties of the alloy had been investigated. The results show that the long range order parameter of L12structure decreased rapidly in the early stage of milling. After 5h milling, the material is completely disordered, forming a FCC solid solution. By further milling to 60h, the powder transformed to purely amorphous state. Bulk specimens were fabricated from the disorder FCC powder by hot pressing at high temperature. The microstructure of the consolidated alloy consists of fine equiaxed grains with tiny particles of dispersed Al2O3at grain boundaries and in the grains. Remarkable improvement of strength and promising compressive ductility are exhibited by this experimental alloy. The yield strength(σ0.2)and fracture strength(σb)are 546 MPa and 1 471 Mpa respectively, and the compressive ductility(δp)is 17%.
Key words: Al67Mn8Ti25alloy high-energy ball milling powder metallurgy structure evolution intermetallic compound