流变铸轧AZ91D镁合金半固态组织演变特点  

Evolution of Microstructural Characteristics of Rheo-rolling Semi-solid AZ91D Magnesium Alloy

作　　者：程尚栩[1] 杨湘杰[2] 郭洪民[1] 谢水生[3] 

机构地区：[1]南昌大学材料科学与工程学院 [2]南昌大学机电工程学院 [3]北京有色金属研究总院

出　　处：《特种铸造及有色合金》2009年第11期1016-1018,共3页Special Casting & Nonferrous Alloys

基　　金：国家自然科学基金资助项目(50804023);有色金属材料制备加工国家重点实验室2007年度开放课题

摘　　要：采用旋转管浇注法制得AZ91D镁合金半固态浆料,在水平双辊铸轧机上进行了流变铸轧试验研究,对铸轧前后组织的特点进行了分析比较。结果表明,铸轧可使初晶更加圆整,620℃浇注温度下,静置时间短,铸轧对初晶圆整化效果更加显著;铸轧后初晶尺寸略微减小,分布更加均匀;铸轧后薄板面上的初晶晶粒密度低于半固态浆料的晶粒密度,620℃浇注温度下,铸轧后晶粒密度显著下降。Semi-solid slurry of AZ91D magnesium alloy was prepared by rotary pouring method,and rheo-rolling experiment was carried out on a horizontal twin-roll caster,furthermore,the microstructure of the alloy before and after rheo-rolling process was analyzed comparatively.The results show that primary phase becomes more rounds after rheo-rolling process.Desirable spheroidization can be observed in the rheo-rolled AZ91D magnesium alloy with pouring at 620℃ and holding for a short time.Average grain size of primary phase is slightly decreased with more homogeneous distribution in the rheo-rolled AZ91D magnesium alloy.Grain density of primary phase in the rheo-rolled AZ91D magnesium alloy sheet surface is less than that in semi-solid slurry.Furthermore,grain density is significantly reduced in the alloy with pouring at 620 ℃ after rheo-rolling.

关 键 词：流变铸轧 半固态 镁合金 

分 类 号：TG27[金属学及工艺—铸造] TG339