薄壁铝合金压铸充型沿程的组织与力学性能  

Microstructure and mechanical properties along fluidity length of thin-wall aluminum alloy under high pressure die casting conditions

作　　者：朱必武[1,2] 李落星[1,2] 刘筱[1,2] 王水平[1,2] 张立强[1,2] 

机构地区：[1]湖南大学汽车车身先进设计与制造国家重点实验室,长沙410082 [2]湖南大学机械与运载工程学院,长沙410082

出　　处：《中国有色金属学报》2012年第8期2163-2173,共11页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金面上项目(51075132);湖南省杰出青年基金(09JJ1007);高等学校博士学科点专项科研基金(20090161110027)

摘　　要：采用压铸制备薄壁AlSi10MnMg铝合金铸件,用金相技术、密度、拉伸性能等分析方法讨论浇注温度对薄壁铝合金压铸充型沿程的组织与力学性能的影响。结果表明:随着浇注温度的升高,试样流动临界长度增加,气孔增多,α(Al)枝晶变细,抗拉强度和断后伸长率先增加后降低。随着充型沿程流动长度的增加,气孔先减少后增加,α(Al)枝晶变化不大。当浇注温度为650和680℃时,试样抗拉强度和断后伸长率沿充型流动长度的增加而减小;当浇注温度为710和740℃时,试样抗拉强度和断后伸长率沿充型流动长度的增加变化较小。The thin-wall AlSi10MnMg aluminum alloy samples were prepared by high pressure die casting. The effects of pouring temperature on the microstructure and mechanical properties along the fluidity length were discussed by metallographic techniques, density measurement and tensile tests. The results show that, with the pouring temperature increasing, the critical fluidity length and porosity increase, and σ（Al） grain size decreases and the ultimate tensile strength and elongation to fracture increase firstly, and then decrease. With the increase of the fluidity length, the porosity decreases firstly and then increases, but the σ（Al） grain size is insignificant. The ultimate tensile strength and elongation to fracture decrease along the fluidity length under pouring temperatures of 650 and 680 ℃. However, the difference of the ultimate tensile strength and elongation to fi＇acture along the fluidity length under pouring temperatures of 710 and 740 ℃ is insignificant.

关 键 词：薄壁铝合金 压铸 组织 力学性能 

分 类 号：TG249.2[金属学及工艺—铸造]