机械搅拌对半固态7075铝合金浆料组织的影响  

Effect of Stirring Parameters on Microstructure of Semi-solid 7075 Aluminum Alloy Slurry

作　　者：李亚庚 毛卫民[1] 朱文志[1] 杨斌[1] 宋晓俊[1] 

机构地区：[1]北京科技大学铸造研究所

出　　处：《特种铸造及有色合金》2015年第7期717-719,共3页Special Casting & Nonferrous Alloys

基　　金：国家重点基础研究发展计划(973计划)资助项目(2011CB6063021);国家自然科学基金资助项目(51074024)

摘　　要：使用机械搅拌式半固态流变仪研究了工艺参数对半固态7075铝合金组织的影响。结果表明,等温搅拌条件下,搅拌时间越长,半固态7075合金组织的固相颗粒尺寸越小,晶粒越圆整;剪切速率越大,半固态7075铝合金初生固相的晶粒尺寸越小,晶粒球化程度越高。连续冷却搅拌条件下,冷却速率越大,固相颗粒尺寸越小,但枝状晶较多。搅拌之后保温条件下,随着保温时间延长,半固态7075铝合金初生固相的晶粒形貌越圆整,但晶粒尺寸越大。Effects of stirring parameters on microstructure of semi-solid 7075 aluminum alloy slurry were investigated by the Couette Viscometer.It is found that size of the primary solid particles is decreased and spheroidized gradually with the increase of the stirring time and the shearing rate during the isothermal stirring process.During continuous cooling process,with the increase of the cooling rate,the primary grain size is refined gradually with the increase of dendrite particles.During the isothermal holding process,the solid particles are granulated and coarsened with increasing in holding time.

关 键 词：晶粒尺寸 搅拌时间 剪切速率 冷却速率 保温时间 

分 类 号：TG292[金属学及工艺—铸造]