A356铸造铝合金轮毂组织与性能分析  

Analysis on microstructure and properties of A356 cast aluminum alloy wheel hub

作　　者：毛建辉[1] 张玉贤[1] 姜路文 曲攀 MAO Jian-hui;ZHANG Yu-xian;JIANG Lu-wen;QU Pan(School of Mechanical and Electrical Engineering,Quzhou College of Technology,Quzhou 324000,Zhejiang,China;College of Mechanical Engineering,Hebei University of Technology,Tianjin 300131,China)

机构地区：[1]衢州职业技术学院机电工程学院,浙江衢州324000 [2]河北工业大学机械工程学院,天津300131

出　　处：《中国冶金》2021年第5期66-71,共6页China Metallurgy

基　　金：国家自然科学基金资助项目(51275152);浙江省教育科学规划课题资助项目(2021SB064);衢州市科技计划资助项目(2019k19)。

摘　　要：分析了A356合金和经T6热处理的A356-T6合金的组织与性能,结果表明,A356-T6合金的整体抗拉强度几乎不受固溶时间的影响,且其屈服强度和抗拉强度显著提高,但随着固溶时间的增加,其伸长率逐渐降低。随着热处理时效从4增加至48 h, A356-T6合金的屈服强度增加了约183.25%,抗拉强度增加了约71%。通过对铸态A356轮毂的弯曲力矩耐久性试验,由SEM分析结果可知,疲劳裂纹存在区域有组织不均匀的现象,判断此部位造型设计与冷却系统设计不良,导致此区域形成热点成为最后凝固区,造成该区域的共晶Al-Si相堆积及粗化共晶Si存在。因此,改善铸态组织不均与微缩孔形成以及降低铁基金属间化合物,有助于改善A356合金的组织与力学性能。The microstructure and properties of A356 alloy and A356-T6 alloy after T6 heat treatment were analyzed. The results showed that the overall tensile strength of A356-T6 alloy was almost not affected by solid solution time, and its yield strength and tensile strength were significantly improved, but with the increase of solid solution time, the elongation decreased gradually. With the increase of heat treatment aging time from 4 to 48 h, the yield strength of A356-T6 alloy increased by about 183.25%, and the tensile strength increased by about 71%. Through the bending moment durability test of the cast A356 wheel hub, results of SEM analysis showed that there was uneven microstructure in the fatigue crack area. It was mainly judged that the shape design and cooling system design of this area were not good, resulting in the formation of hot spots in this area and becoming the final solidification area, and resulting in the accumulation of eutectic Al-Si phase and the coarsening of eutectic Si in this area. Therefore, it is helpful to improve the microstructure and mechanical properties of A356 alloy by improving the as-cast microstructure unevenness and microporosity formation and reducing the iron-based intermetallic compounds.

关 键 词：A356合金 热处理 轮毂 疲劳试验 疲劳失效 

分 类 号：TG146.21[一般工业技术—材料科学与工程]