铸态和T6热处理Al-10Si-0.5Mg-0.5Mn挤压铸造铝合金的组织和力学性能  

Microstructure and Mechanical Properties of As-Cast and T6 Heat-Treated Al-10Si-0.5Mg-0.5Mn Squeezing Cast Aluminum Alloy

作　　者：闫俊 石帅 范卫忠 高伟全 罗远文 程汉明 周建明 YAN Jun;SHI Shuai;FAN Wei-zhong;GAO Wei-quan;LUO Yuan-wen;CHENG Han-ming;ZHOU Jian-ming(Huajin New Material Research Institute(Guangzhou)Co.,Ltd.,Guangzhou 510115,Guangdong,China)

机构地区：[1]华劲新材料研究院(广州)有限公司,广东广州510115

出　　处：《铸造》2021年第12期1391-1396,共6页Foundry

摘　　要：采用挤压铸造的成形方式制备出Al-10Si-0.5Mg-0.5Mn合金,利用金相显微镜、扫描电镜和能谱分析等手段研究了铸态和不同热处理工艺对合金的微观组织与力学性能的影响。结果表明,挤压铸造Al-10Si-0.5Mg-0.5Mg合金铸态组织细小致密,晶粒大小分布不均,白色的长条状及块状AlFeMnSi相分布在晶界处。经过T6热处理后大部分共晶硅及AlFeMnSi相的球化效果较好,但存在明显的共晶硅偏聚区域及少量块状AlFeMnSi相。经优化后得到合金的最佳热处理工艺为:固溶535℃×4h+时效160℃×6h,该工艺下合金的共晶硅分布较均匀,长条状及块状AlFeMnSi相转化成近球状甚至点状纳米级粒子,合金硬度为HB115,断后伸长率为9.4%,相对于铸态分别提升53.3%和77.3%。Al-10Si-0.5Mg-0.5Mn alloy was prepared by squeeze casting. The effects of as-cast state and different heat treatment processes on the microstructure and mechanical properties of the alloy were studied by means of metallographic microscope, scanning electron microscope and energy spectrum analysis. The results show that the microstructure of as-cast squeezing cast Al-10 Si-0.5 Mg-0.5 Mg is fine and dense, the grain size distribution is uneven, and long white AlFeMnSi and massive AlFeMnSi phases are distributed at grain boundaries. After the T6 heat treatment, the spheroidization effect of most eutectic silicon and AlFeMnSi phase is good, but there are obvious eutectic silicon gathering region and a few lumps of AlFeMnSi phase. After optimization,the optimal heat treatment process of the alloy is as follows: solution treatment at 535 ℃ × 4 h+aging at 160 ℃ ×6 h,with which the eutectic silicon distribution of the alloy is uniform, and the long and massive AlFeMnSi phases are transformed into nearly spherical or even point-like nano-particles. The hardness of the alloy is up to HB115, and the elongation after fracture is 9.4%, being increased by 53.3% and 77.3%, respectively,compared with the as-cast alloy.

关 键 词：挤压铸造 Al-10Si-0.5Mg-0.5Mn合金 热处理 强化相 硬度 

分 类 号：TG146.21[一般工业技术—材料科学与工程]