固溶时效工艺对铸造A357铝合金组织与性能的研究  

Research on Solution and Aging Process of Microstructure and Properties of A357 Cast Alloy

作　　者：吴恺威 雍学超 周细应[1] 王付鑫[1] 李绍伟[1] WU Kaiwei;YONG Xuechao;ZHOU Xiying;WANG Fuxin;LI Shaowei(College of Materials Engineering,Shanghai University of Engineering Sciences,Shanghai 201620,China)

机构地区：[1]上海工程技术大学材料工程学院,上海201620

出　　处：《铸造技术》2020年第12期1113-1116,1133,共5页Foundry Technology

摘　　要：利用光学显微镜(OM)、扫描电子显微镜(SEM)等手段研究了固溶、时效工艺对A357铸造铝合金组织与性能的影响。结果表明,A357铸造铝合金的显微组织由α-Al基体、共晶硅及Mg2Si相组成。在540℃×4 h固溶和145℃×4 h时效处理后,共晶硅更加圆整和均匀,共晶硅、Mg2Si相均匀分散在α-Al基体晶界处,拉伸性能大幅度提高,使A357铝合金铸件性能达到预期要求。A357铸造铝合金的最佳热处理工艺为,固溶处理:(540±3)℃×4 h;时效处理:(145±5)℃×4 h。The effects of solution and aging process on the microstructure and properties of A357 aluminum alloy were studied by means of optical microscope(OM)and scanning electron microscope(SEM).The results show that the microstructure of A357 cast aluminum alloy is composed ofα-Al matrix,eutectic silicon and Mg2Si phase.After solid solution at 540℃×4 h and aging treatment at 145℃×4 h,eutectic silicon is more round and uniform,eutectic silicon and Mg2Si phases are uniformly dispersed at the grain boundary ofα-Al matrix,and the tensile property is greatly improved,so that the performance of A357 aluminum alloy casting reach the expected requirements.The optimal heat treatment process of A357 cast aluminum alloy is:solid solution treatment:(540±3)℃×4 h;Aging treatment:(145±5)℃×4 h.

关 键 词：A357 铸造铝合金 固溶 人工时效 组织 

分 类 号：TG156.94[金属学及工艺—热处理] TG113[金属学及工艺—金属学]