A4020铝合金活塞的SIMA法制备及微观组织研究  

Preparation of A4020 Aluminum Alloy Piston by SIMA Method and Its Microstructure

作　　者：祁红璋[1] 李成魁[1] 严彪[1] 蒋凯雁[1] 

机构地区：[1]同济大学材料科学与工程学院,上海市金属功能材料开发应用重点实验室

出　　处：《特种铸造及有色合金》2009年第9期810-812,共3页Special Casting & Nonferrous Alloys

摘　　要：采用SIMA(Strain Induced Melt Activation-应变诱发熔化激活)半固态成形的方法进行了A4020铝合金活塞零件的触变铸造,并研究了固态挤压前、后的微观组织和二次加热过程中组织的演变。结果表明,经固态挤压塑性变形后,活塞零件的粗大树枝晶被打碎,其微观组织形态由树枝状变为流线状;二次加热过程中组织演变为:不规则块状组织,组织分离局部球化和完全球化。A4020 aluminum alloy piston was produced by thixo-forming method,in which alloy slurry was prepared by SIMA (strain induced melt activation). Meanwhile,microstructure of the alloy before and after extrusion and microstructural evolution during reheating were observed by OM (optical microscope). The results show that microstructure of the extruded alloy is converted from dendrite into streamline structure. In addition,the microstructure in process of reheating is evolved from irregular block structure into structure separation and into partial spheroidization finally into completely spheroidization.

关 键 词：半固态成形 应变诱发熔化激活(SIMA) 微观组织 A4020铝合金 

分 类 号：TG249.9[金属学及工艺—铸造]