冷却速度对Mg_2Si增强过共晶Al-Si合金组织与性能的影响  

Effect of Cooling Rate on Microstructure and Properties of Mg_2Si Particle Reinforced Hypereutectic Al-Si Alloy

作　　者：刘萍[1] 

机构地区：[1]上海交通大学材料科学与工程学院,上海200030

出　　处：《铸造技术》2006年第7期715-718,共4页Foundry Technology

摘　　要：采用液态熔融法制备Mg2Si增强过共晶Al-Si合金自生复合材料。研究了冷却速度、稀土(Pr)变质处理对铸态显微组织与性能的影响。结果表明,在液相线附近,冷却速度快,晶粒均匀细小;稀土(Pr)变质剂对初生硅及共晶组织均有明显的细化效果,并细化Mg2Si、改变其形貌与尺寸,可显著提高合金的力学性能。The Mg2Si particle reinforced hypereutectic AI-Si alloy in-situ composites are manufactured by liquid pouring. The effects of cooling rates and rare earth modification on casting microstructure of the alloy manufactured are investigated. The results indicate that the size and the shape of grain become finer and more uniform with increase of cooling rate. The size of grain obtained from cooling in the water is finer than that of other cooling methods. Rear earth Pr has an obvious effect on the refinement of primaryαsiliconand eutectic structure, meanwhile, it refines Mg2Si phase and changes shape and sizes of Mg2Si phase, thus improve the mechanical properties of alloy significantly.

关 键 词：MG2SI 过共晶AL-SI合金 自生复合材料 显微组织 

分 类 号：TG113[金属学及工艺—物理冶金]