一种基于位错机制的动态应变时效模型  

A DISLOCATION-MECHANICS-BASED CONSTITUTIVE MODEL FOR DYNAMIC STRAIN AGING

作　　者：郭扬波[1] 唐志平[1] 程经毅[1] 

机构地区：[1]中国科学技术大学力学与机械工程系,合肥230027

出　　处：《固体力学学报》2002年第3期249-256,共8页Chinese Journal of Solid Mechanics

基　　金：中国科学院回国工作基金资助

摘　　要：动态应变时效是由位错与溶质原子的相互作用引起的 ,只考虑位错与位错芯内的溶质原子 (位错芯气团 )的相互作用 ,在位错热激活运动机制的Zerilli Armstrong热粘塑性本构模型的基础上 ,加以改进 ,并加入位错和位错芯气团的相互作用的影响 ,建立了一种可定量描写动态应变时效现象的本构模型 .所得到的本构模型以Zerilli Armstrong模型为基础 ,不仅可以描写动态应变时效现象 ,还可以描写金属在很大温度 (77K - 10 0 0K)和应变率 (10 -4 - 10 4 s-1)范围内的力学行为 .本构模型对钽的拟合和预测与实验结果有较好的吻合 .Dynamic strain aging is caused by the interaction between the moving dislocations and the mobile solute atoms. Only considered the interaction between moving dislocations and mobile solute atoms in dislocation core area (core atmosphere). To get the constitutive relation which can describe the dynamic strain aging phenomenon, improved the Zerilli-Armstrong dislocation-mechanics-based thermal viscoplastic constitutive relation, and added the effect of the interaction between the moving dislocations and core atmosphere. Because the constitutive relation established is based on the Zerilli-Armstrong relation, it can describe not only the dynamic strain aging phenomenon, but also the mechanical behavior of metals in a broad range of temperature (77 K～1000 K) and strain rate (10 -4～10 4 s -1). The prediction for tantalum fits well with the experimental data.

关 键 词：位错机制 动态应变时效模型 溶质原子 位错芯气团 钽 材料力学 

分 类 号：TG111[金属学及工艺—物理冶金]