不同固溶处理对Cu-Cr系合金组织和性能的影响
Effect of different solid solution treatments on microstructure and properties of Cu-Cr alloy
杨旗 1王志磊 2肖星宇 1谢建新2
作者信息
- 1. 北京科技大学 新材料技术研究院 现代交通金属材料与加工技术北京实验室,北京 100083;北京科技大学 新材料技术研究院 材料先进制备技术教育部重点实验室,北京 100083
- 2. 北京科技大学 新材料技术研究院 现代交通金属材料与加工技术北京实验室,北京 100083;北京科技大学 新材料技术研究院 材料先进制备技术教育部重点实验室,北京 100083;辽宁材料实验室 材料智能技术研究所,沈阳 110004
- 折叠
摘要
热处理工艺调控是提升Cu-Cr系合金性能的有效方法.Cu-Cr系合金的固溶工艺大多选择温度较低的Cu-Cr两相区进行,导致Cr相固溶程度不完全,抑制后续析出强化效果.本研究提出采用高温单相区固溶工艺改善析出强化效果,主要研究不同固溶工艺(Cu-Cr两相区(950℃,4 h)和Cu单相区(1050℃,6 h))对Cu-Cr系合金组织和性能的影响.采用电子探针(EPMA)对两种固溶工艺后的元素分布进行表征,并对峰值时效态合金的微观结构采用XRD和TEM进行表征分析.结果表明:与两相区固溶相比,单相区固溶后铸态Cr相充分固溶,时效过程中更多纳米Cr相弥散析出;合金力学性能相比两相区固溶后峰值时效态有较大提升,其中屈服强度提升29.3％,抗拉强度提升25.6％,而导电率并未明显下降.强度理论计算结果表明,析出强化所贡献的屈服强度增量为323.4 MPa,贡献56.9％,析出强化是本研究中最主要的强化机制.
Abstract
Heat treatment is well-known to be effective to improve the performance of Cu-Cr alloys.The solid solution process of Cu-Cr alloys mostly selects the lower temperature Cu-Cr two-phase region,resulting in incomplete dissolution of Cr phase and inhibiting subsequent precipitation strengthening effect.A high-temperature single-phase region solid solution process was proposed to improve the strengthening effect.The effects of different solid solution processes((950℃,4 h)in the two-phase region and(1050℃,6 h)in the single-phase region)on the microstructure and properties of Cu-Cr alloy were comparably studied.The element distribution after two solid solution processes was characterized by electron probe microanalyzer(EPMA),and the microstructure of the peak-aged alloy was characterized and analyzed by XRD and TEM.The results show that,compared with solid solution in the two-phase region,the cast Cr phase is fully dissolved after solid solution in the single-phase region,and more nano Cr phases precipitate during aging.The mechanical properties of the alloy are significantly improved compared to those of the alloy at the peak-aged state after solid solution in the two-phase region,the yield strength increases by 29.3％and tensile strength increases by 25.6％,while the electrical conductivity does not decrease significantly.Strength theory calculations results indicate that the yield strength increment contributed by precipitation strengthening is 323.4 MPa,accounting for 56.9％,which is the most significant strengthening mechanism in this study.
关键词
Cu-Cr合金/单相区固溶/析出强化/导电率Key words
Cu-Cr alloy/solid solution in single-phase region/precipitation strengthening/electrical conductivity引用本文复制引用
基金项目
国家重点研发计划资助项目(2021YFB3803100)
出版年
2024
NETL
NSTL
万方数据