扩展路径低温ECAP及时效热处理对Cu0.6Cr合金的组织和性能影响

Effect of Low-Temperature ECAP with Extended Route and Aging Heat Treatment on Structure and Properties of Cu0.6Cr Alloy

摘要:

采用光学显微镜和X射线衍射仪对Cu0.6Cr合金经低温扩展路径等通道转角挤压（ECAP）后的组织演变规律进行了研究。采用扫描电子显微镜和能谱仪研究了Cu0.6Cr合金经不同时效热处理条件后的晶粒大小、析出相分布规律和断裂特征。并且分别测试了合金经低温ECAP和低温ECAP+时效热处理后的抗拉伸强度、硬度和导电率。结果表明，Cu0.6Cr合金经低温ECAP变形后形成明显细化且相互交割的纤维组织，并且合金在变形中始终保持（111）面的择优取向。时效热处理的合金变形量越大，析出相的数目和尺寸就越大，第二相析出速率也越快。5道次合金经450 ℃时效2 h后的抗拉伸强度为568.1 MPa，维氏硬度为1624.8 MPa，导电率为82%IACS。

Abstract:

The optical microscope and X-ray diffractometer were used to study the microstructure evolution of Cu0.6Cr alloy prepared by low-temperature equal channel angular pressing (ECAP) with extended route. The scanning electron microscope and energy dispersive spectrometer were used to study the grain size, precipitate distribution, and fracture characteristics of Cu0.6Cr alloy after different aging heat treatments. The tensile strength, hardness, and conductivity of the alloy prepared by low-temperature ECAP and low-temperature ECAP+aging heat treatment were analyzed. Results show that the obviously refined and intersecting fibrous structure is formed in Cu0.6Cr alloy after low-temperature ECAP. The alloy maintains the preferential orientation of (111) crystal plane during deformation. In the aging heat treatment, the larger the alloy deformation, the larger the number and size of the precipitates, and the faster the precipitation rate of the secondary phase. After aging at 450 °C for 2 h, the tensile strength of the 5-pass alloy is 568.1 MPa, the Vickers hardness is 1624.8 MPa, and the conductivity is 82%IACS.