摘要
对钛合金同时进行了绝热剪切带的显微观察和动态本构关系的宏观研究,发现材料在冲击载荷下的绝热剪切是一速率相关过程,而对应的热粘塑性动态失稳准则是一多变量准则,相联系地还讨论了材料在冲击载荷下的动态屈服准则和动态断裂准则,指出在给定环境温度下都类似地是双变量准则。
By the microscopical observation of adiabatic shear bands for Titanium alloys and by the macroscopical investigation of the associateddyn-amic,constitutive relation, it is found that the adiabatic shearing is a rate-dependent process,and the corresponding criterion of dynamic thermo-viscopla-. stic instability is a criterion with multi-control-variahles. For a given environmental temperature, it is shown that the theoretical predictions of a proposed dual-control-variablesc(critical strain versus strain-rate)criterion arein good agreement with the experimental data. Taking the environment tem-perature as an additional variable, such a criterion can then be generalizedto a tri-control-variables one.It is pointed out too that the dynamic yield criterion and the dynamic strength criterion under impact loading should be the dual-control-variables ones, for a given environmental temperature. The corresponding criteria suitable to the rate independent elastic-plastic wave propagation are presented too.
出处
《力学学报》
EI
CSCD
北大核心
1989年第S1期142-147,共6页
Chinese Journal of Theoretical and Applied Mechanics
关键词
冲击载荷
动态失稳
动态屈服
绝热剪切
热粘塑性`
dynamic instability, adiabatic shearing, dynamic yield, the-rmo-viscoplasticity, impact loading.