(1. 河南科技大学材料科学与工程学院,洛阳 471023; 2. 河南省有色金属共性技术河南省协同创新中心,洛阳 471023)
摘 要: 采用真空熔炼的方法制备Cu-Cr-Zr合金,研究合金的时效析出行为;借助高分辨透射电镜对合金时效析出相的组织形态进行分析,探讨合金的时效强化机制。结果表明:Cu-0.36Cr-0.03Zr合金经450 ℃时效4 h后获得较好综合性能,合金硬度和导电率分别达到为156 HV和82.62 %IACS;通过微观分析确定经450 ℃时效4 h后合金中析出相为面心立方Cr相,且与基体保持共格关系;当时效时间延长至8 h时,合金中面心立方Cr相转变为体心立方Cr相;经450 ℃时效4 h后合金强度与硬度的提高主要由共格应变强化所造成。
关键字: Cu-Cr-Zr合金;时效处理;析出相;共格应变强化
(1. School of Materials Science and Engineering, Henan University of Science and Technology, Luoyang 471023, China; 2. Henan Province Collaborative Innovation Center of Nonferrous Metals, Luoyang 471023, China)
Abstract:The Cu-Cr-Zr alloy was fabricated by vacuum melting, and the investigation on precipitation behavior was conducted. The morphology of precipitation was observed by means of high resolution transmission electron microscope (HRTEM), and the aging strengthening mechanism of alloy was discussed. The results show that a better comprehensive performance of the alloy aged at 450 ℃ for 4 h is obtained, the microhardness and electrical conductivity of the alloy are 156 HV and 82.62 %IACS, respectively. The face-centered cubic(FCC) Cr precipitates are found in the alloy aged at 450 ℃ for 4 h through the micro-analysis. As times increases to 8 h, the face-centered cubic Cr-phases transform into body-centered cubic(BCC) Cr-phases. The high strength of the alloy aged at 450 ℃ for 4 h mainly attributes to coherent strain strengthening mechanism.
Key words: Cu-Cr-Zr alloy; aging treatment; precipitate; coherent strain strengthening