CDS制备过共晶Al-Si合金工艺参数的研究  

Study on Technological Parameters of Controlled Diffusion Solidification for Hypereutectic Al-Si Alloys

作　　者：胡韶华[1] 李元东[1,2] 何明涛[1] 索江龙[1] 马颖[1,2] 

机构地区：[1]兰州理工大学甘肃省有色金属新材料省部共建国家重点实验室,甘肃兰州730050 [2]兰州理工大学有色金属合金及加工教育部重点实验室,甘肃兰州730050

出　　处：《铸造》2012年第11期1291-1295,共5页Foundry

基　　金：国家自然科学基金项目(51064017)

摘　　要：采用液-液混合受控扩散凝固技术(CDS)制备过共晶Al-20%Si(质量分数)合金,研究了混合后熔体保温处理、冷却速度对合金组织的影响。研究表明,熔体混合后未进行保温处理时,初生硅尺寸在60～100μm,且多为五瓣星状和不规则多边形;而进行保温之后,随着保温时间的延长,初生硅的尺寸逐渐减小;保温45 min后,初生硅尺寸在30～50μm,形貌比较圆整;而随着冷却速度的增加,目标合金组织中初生硅尺寸减小,由94.6μm减小到69.65μm,长宽比由1.78增加到4.33。To prepare hypereutectic Al-20%Si alloy, the liquid-liquid mixing controlled diffusion solidification （CDS） was used, and the effect of holding treatment of the melt and cooling rate on the alloy microstructure has been studied. The results show that the primary size is about 60-100 μm without holding treatment and mainly appears in five petal star-shaped and irregular polygon. When the mixing melt is holing nearby the liquids of the target alloy, primary silicon size reduces gradually, the primary size is about 30-50 μm after holding 45 min and the shape is round. With the increase of cooling rate, primary silicon size in the target microstructure reduces from 94.6 μm to 69.65 μm, but the ratio of length to width increases from 1.78 to 4.33.

关 键 词：受控扩散凝固(CDS) 过共晶铝硅合金 保温处理 冷却速度 初生硅 

分 类 号：TG244[金属学及工艺—铸造]