引线框架C19400合金的微观组织、力学性能及残余应力

Microstructure, Mechanical Properties, and Residual Stress of Lead Frame C19400 Alloy

摘要:

系统研究了C19400合金冷轧态和时效态样品的力学性能、微观组织和残余应力。结果表明，轧制态合金的最高抗拉强度可达546 MPa。此外，宏观残余应力和微观残余应力的结果均表明轧制态合金的残余应力更高，这说明残余应力主要是在不均匀的冷轧塑性变形过程中产生，这在核平均取向差（KAM）分布图中得以验证，因为轧制态合金的KAM值高于时效态合金。与此同时，研究揭示了C19400合金宏观与微观织构的演变规律，结果表明，轧制态和时效态合金中的织构类型均为Brass (011)211、Copper (112)111和S (123)634型变形织构和再结晶Cube (001)100织构，并且Copper (112)111织构的强度、体积分数变化与残余应力一致，这说明Copper (112)111织构的存在更有利于残余应力产生。

Abstract:

The mechanical properties, microstructure, and residual stress of the cold-rolled and aged samples of C19400 alloy were systematically studied. The results show that the maximum tensile strength of the rolled alloy can reach 546 MPa. In addition, the results of both macroscopic and microscopic residual stress show that the residual stress of the rolled alloy is higher, indicating that residual stress is mainly generated during the nonuniform cold rolling plastic deformation process. This is verified in the kernel angle misorientation (KAM) distribution map, because the KAM value of the rolled alloy is higher than that of the aged alloy. At the same time, the evolution of macroscopic and microscopic textures in C19400 alloy was revealed. The results show that the texture types in both rolled and aged alloys are Brass (011)211, Copper (112)111, and S (123)634 deformation textures as well as recrystallized Cube (001)100 textures. And the intensity and volume fraction changes of Copper (112)111 textures are consistent with those of residual stress, which indicates that the presence of Copper (112)111 texture is more conducive to the generation of residual stress.