冷却速率对铸态A356铝合金微观组织和拉伸性能的影响  

Effects of cooling rate on microstructure and tensile properties of as-cast A356 alloy

作　　者：吴建华[1,2] 周吉学[1,2] 唐守秋[1] 王金伟[3] 张琳琳[1] 陈燕飞[3] 

机构地区：[1]山东省科学院新材料研究所,济南250014 [2]山东省轻质高强金属材料省级重点实验室(筹),山东省科学院新材料研究所,济南250014 [3]山东省汽车轻量化镁合金材料工程技术研究中心,山东省科学院新材料研究所,济南250014

出　　处：《功能材料》2016年第B12期63-66,共4页Journal of Functional Materials

基　　金：山东省博士基金资助项目(BS2015CL016);山东省科学院青年基金资助项目(2014QN026)

摘　　要：研究不同冷却速率对A356合金铸态微观组织和拉伸性能的影响。结果表明,随着冷却速率的提高:合金二次枝晶间距减小,共晶Si相由粗大的针片状向细小的短棒状或颗粒状转变,合金的拉伸性能得到改善。合金的抗拉强度达到205 MPa,屈服强度达到143 MPa,延伸率达到10.4%。通过控制冷却速率,可细化A356合金的铸态组织,提高合金的拉伸性能。The effects of cooling rate on the microstructure and tensile properties of as-cast A356 alloy were investigated.The results show that the secondary dendrite arm spacing decreased with increaseing of cooling rate. At the same time,the morphology of eutectic silicon in A356 alloy was changed from coarse needle to fine short-rod or particles,and thus resulting in increase of the tensile properties. The tensile strength of 205 MPa,the yield strength of 143 MPa and elongation of 10.4% was obtained for A356 alloy at the high cooling rate. Therefore,controlling cooling rate can refine the microstructure and improve the mechanical properties of as-cast A356 alloy.

关 键 词：冷却速率 A356铝合金 微观组织 拉伸性能 

分 类 号：TG292[金属学及工艺—铸造]