连续挤压Al-Mg合金管的稳定化热处理研究  

Effect of stabilizing heat treatment on Al-Mg alloy tubes by continuous extrusion

作　　者：许秀芝[1] 向茜[1] 谭颖[1] 张宗鹏[1] 郭道强 林高用[1] 

机构地区：[1]中南大学材料科学与工程学院,有色金属材料科学与工程教育部重点实验室,湖南长沙410083 [2]郴州市强旺新金属材料有限公司,湖南郴州423000

出　　处：《轻合金加工技术》2015年第4期55-61,共7页Light Alloy Fabrication Technology

基　　金：中南大学大学生创新训练计划省级项目(201410533301);湖南省科技成果转化与产业化项目(2013CK1003)

摘　　要：采用扫描电镜、能谱分析、透射电镜、金相显微镜、室温拉伸测试、硬度测试、扩口测试等分析手段研究了连续挤压Al-Mg合金管的稳定化热处理工艺。结果表明:通过300℃3 h、空冷的稳定化热处理后,合金管的伸长率为26.6%,扩口率为39.2%,抗拉强度为281 N/mm2,前两者较挤压态依次提高了8.5%和14.6%,抗拉强度稍有下降。这是因为经稳定化热处理后合金中析出了含硅的脆性相和β相。此外,经过稳定化热处理后试样室温拉伸时不均匀变形程度得以改善,且扩口时没有沿焊缝断裂。The stabilizing heat treatment was investigated for A1-Mg alloy tubes by continu- ous extrusion by SEM, EDS, TEM, the optical microscopy, tensile tests, hardness tests and flaring tests. The results show that after tubes are heat treated at 300℃ for 3 h and cooled in air,the elongation is 26.6% and the extension rate is 39.2%. They are 8.5% and 14.6% higher than those of extruded tubes, respectively. However, the tensile strength is 281 N/mm^2. The reason why this value is lower than the tensile strength of extruded tubes is that some silicon-contained brittle phases and 13 phases precipitate after stabilizing heat treatment. After stabilizing heat treatment, the deformation in tensile tests at room temperature be- comes more homogeneous, and in flaring tests appear no fractures along the weld.

关 键 词：连续挤压 Al-Mg合金管 力学性能 稳定化热处理 

分 类 号：TG379[金属学及工艺—金属压力加工]