旋转磁场作用下Pb-Sn合金的凝固组织  

Solidification Structure of Pb-Sn Alloy in Rotating Magnetic Field

作　　者：高文帅[1] 陈长乐[1] 陈钊[1] 朱建华[1] 

机构地区：[1]西北工业大学陕西省凝聚态结构与性质重点实验室

出　　处：《特种铸造及有色合金》2008年第3期176-179,共4页Special Casting & Nonferrous Alloys

基　　金：国家自然科学基金重点项目(50331040)

摘　　要：采用自行设计的旋转磁场,研究了在不同转速和不同磁感应强度下旋转磁场对Pb-45Sn亚共晶和Pb-64Sn过共晶合金凝固组织的影响,并与常规条件下的凝固组织进行对比。试验结果表明,对Pb-45Sn亚共晶,旋转磁场可以明显的碎断枝晶,细化晶粒;对Pb-64Sn过共晶,旋转磁场可以消除常规条件下的重力偏析,枝晶间的共晶组织被粗化,并有团状组织生成。试验发现,随着磁感应强度和转速的增大,Pb-45Sn亚共晶和Pb-64Sn过共晶凝固组织中等轴晶的数目均增多。Solidification structures of hypereutectic Pb-45Sn alloy and hypoeutectic Pb-64Sn in rotating magnetic field with different rotating velocity and magnetic flux density were observed based on a self-designed rotating magnetic field apparatus,and were compared with those of alloy in conventional condition.The results reveal that the rotating magnetic fileld can greatly refine grain size in the hypereutectic Pb-45Sn alloy due to broken dendrite while it can coarsen the eutectic structure in inter-dendrite with the creation of bulk structure due to suppressing the gravity-induced macro-segregation.In addition,with the increase of both magnetic flux density and rotating velocity,the numbers of equiaxed grain in solidification structure of both hypereutectic Pb-45Sn alloy and hypoeutectic Pb-64Sn alloy are increased.

关 键 词：旋转磁场 PB-SN合金 流动 枝晶碎断 

分 类 号：TG111.4[金属学及工艺—物理冶金]