摘要
用挤压铸造、挤压比仅为１０∶１的挤压以及进一步的轧制成功地制备了具有高应变速率超塑性行为的βＳｉＣ晶须增强ＬＹ１２复合材料。该复合材料晶粒细小，约为２μｍ；在温度为８０３Ｋ和初始应变速率为１．１×１０－１ｓ－１时，延伸率达３５０％，应变速率敏感系数ｍ值约为０．３５；超塑性变形的主要机制是细小晶粒的晶界滑动，适当的微量液相有利于该复合材料的高应变速率超塑性。
A SiC whisker reinforced LY12 aluminum composite expected to exhibit high strain rate superplasticity has been successfully fabricated by squeeze casting and rolling after extrusion with a low extrusion ratio of 101. The asprocessed composite has a fine grain size of about 2 m, and exhibits a maximum total elongation of 350% and a strain rate sensitivity of about 0.35 at the initial strain rate of 1.110-1s-1 at 803 K. The dominant process of superplastic deformation is fine grain boundary sliding, and an appropriately small amount of liquid phase can enhance the high strain rate superplasticity of the composite.
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
1999年第2期231-235,共5页
The Chinese Journal of Nonferrous Metals
基金
国家自然科学基金
关键词
高应变速率
超塑性
铝基
复合材料
挤压铸造
high strain rate superplasticityaluminum matrix compositessqueeze casting
