用行波电磁搅拌制备半固态AlSi7Mg合金浆料  

Preparation of semi-solid AlSi7Mg alloy slurry through traveling-wave electromagnetic stirring

作　　者：赵振铎[1] 毛卫民[1] 钟荣茂[1] 

机构地区：[1]北京科技大学材料科学与工程学院材料加工系,北京100083

出　　处：《材料研究学报》2008年第4期369-373,共5页Chinese Journal of Materials Research

基　　金：国家高新技术研究发展规划项目2006AA03Z115;国家重点基础研究规划项目2006CB605203资助项目~~

摘　　要：用低过热度浇注和弱行波电磁搅拌工艺制备半固态AlSi7Mg合金浆料,研究了浇注温度和搅拌功率对其初生α-Al形貌的影响.结果表明,用该工艺可制备初生α-Al形貌呈小而圆整的球状晶粒、组织分布均匀、较大尺寸(直径为127 mm)的半固态AlSi7Mg合金浆料.浇注温度合适,短时间弱电磁搅拌(8 s左右)就可获得初生α-Al形貌大部分为球状,组织分布比较均匀的浆料组织.浇注温度一定,适当提高搅拌功率可明显改善初生α-Al的形貌,但是过高的搅拌功率并不能使初生α-Al的形貌进一步改善.用该工艺制备的半固态AlSi7Mg合金浆料,从其边部到心部的径向组织初生α-Al形貌经历了一个从枝晶组织向蔷薇状组织再向球状组织转变的过程.The semi--solid AISiTMg alloy slurry with larger size was prepared by the low superheat pouring and traveling-wave electromagnetic stirring in this paper. The effects of pouring temperature and stirring power on the shape of the primary α-Al grains of the semi-solid AlSi7Mg alloy slurry with larger size were studied. The results show that an ideal microstructure of the semi--solid AlSi7Mg alloy slurry with 127mm in diameter prepared by this preparation method can be obtained and that the proper pouring temperature, stirring power and stirring time are respectively 630 ℃, 1.72 kW and about 8s. When the pouring temperature is fixed, appropriately raising the stirring power can gain a better shape of primary α-Al grains, but if the stirring power is increased to a certain value, the shape of the primary α-Al grains can not be obviously improved. According to the radial microstructure distribution of the semisolid AISi7Mg alloy slurry with larger size manufactured by this method, the shape of the primary α-Al grains experience a transition from dendritic-like grains to rosette-like grains and spherical grains from the edge to the core of slurry.

关 键 词：金属材料 半固态 低过热度浇注 电磁搅拌 初生Α-AL ALSI7MG合金 

分 类 号：TG146[一般工业技术—材料科学与工程] TG244[金属学及工艺—金属材料]