摘要
从拉伸变形的状态方程和力学基本理论出发，导出了塑性和超塑性拉伸变形ｍξ、ｍｖ 和ｍＦ（ｍξ、ｍｖ。和Ｆ分别为恒应变ξ、恒变形速度ｖ和恒载荷Ｆ的应变速率敏感性指数）的函数表达式，而且理论计算值与典型超塑性合金ＺｎＡ１５的试验数据吻合，这便从理论上解答了“拉伸变形应变速率敏感性指数的力学涵义及其规范测量”一文从试验上提出的问题，即：为什么ｍξ、ｍｖ和ｍＦ随应变速率ξ的变化规律互不相同，甚至出现了ｍＦ会大于１，ｍｖ会是负值的反常结果。对这些问题的理论解答便进一步揭示了ｍ值的力学本质。
Functional expressions of mξ,mｖ,and mF(They are respectively strain rate sensitivity index under fixed strain ξ, strain rate sensitivity index under foxed forming velocity ｖand strain rate sensitivity index under foxed load F)in plastic and superplastic deformation from the state equation and the basic mechanial tyeory are deduced.Furthermore,experimental data of typical superplastic alloy ZnA15 are consistent with the theoretical value .Thus,the probloem-why mξ,mｖand mF are different wity ξ changing, even obtain abnormal result that the value of mF is more than 1 and the value of mｖ is negative- is solved theretically,which is put forward experimentally .Then mechanical essence of m value is revealed further.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2001年第3期5-10,共6页
Journal of Mechanical Engineering
基金
国家自然科学基金(59835190)
