SiC颗粒、保温时间对SiC_P/AZ61复合材料半固态组织的影响  

Effect of SiC particle and isothermal holding time on microstucture evolution of SiC_P/AZ61 composites in semi-solid

作　　者：张发云[1] 闫洪[2] 

机构地区：[1]新余学院,新余338004 [2]南昌大学先进成形制造及模具研究所,南昌330029

出　　处：《塑性工程学报》2010年第3期55-60,共6页Journal of Plasticity Engineering

基　　金：国家自然科学基金资助项目(50465003;50765005);江西省自然科学基金资助项目(2007GZC1826);江西省教育厅资助项目

摘　　要：研究SiC颗粒、保温时间对SiCP/AZ61复合材料半固态组织的影响,并探讨复合材料等温过程中半固态组织演变机理。结果表明,SiCP/AZ61复合材料在温度595℃,不同保温时间(0min～90min)下,其组织的演变过程为,枝晶臂合并→大块状组织→晶界处局部熔化分离→晶粒组织球化→球状组织缓慢长大。在温度595℃,保温30min～60min时,SiCP/AZ61复合材料可以获得最佳的半固态组织;与AZ61基体合金相比,由于SiC颗粒的加入,使得SiCP/AZ61复合材料在等温热处理过程中的半固态组织更为细小,并且随着SiC颗粒体积分数增加,其半固态组织中球状颗粒的尺寸越小。Effect of SiC particle and isothermal holding time on microstucture evolution of SiCP/AZ61 composites in semi-Solid was studied,and evolution mechanism of semisolid microstucture of composites during semi-solid isothermal heat-treatment was discussed.The results indicated that the process of microstucture evolution of SiCP/AZ61 composites at 595 ℃ for different isothermaI holding times（0min～90min） experienced successively as：rapid merging of secondary dendritic arms→ massive microstucture → melting of local grain boundary and resulting in microstucture separation→ spheroidization of grain→ gradual growth of globular microstructure.Considering synthetically,after isothermaI holding at 595℃ for 30 t0 60min may obtain favorable microstucture of semi-solid.In comparing with that of the monolithic AZ61alloy,the microstucture of semi-solid of SiCP/AZ61 composites during isothermal heat-treatment is finer as a result of entering of SiC particle,and the globular grain size in the microstucture of semi-solid further decreases with the increase of SiC particle volume fraction.

关 键 词：SiCP/AZ61复合材料 组织演变 保温处理 半固态 

分 类 号：TG331[金属学及工艺—金属压力加工]