Solidification process and microstructure evolution of bulk undercooled Co-Sn alloys  

大体积深过冷Co-Sn合金的凝固过程与组织演化(英文)

作　　者：刘礼[1,2] 马晓丽[3] 黄起森[1] 李金富[1] 程先华[2] 周尧和[1] 

机构地区：[1]上海交通大学材料科学与工程学院,金属基复合材料国家重点实验室,上海200240 [2]上海交通大学机械与动力工程学院,上海200240 [3]上海交通大学材料科学与工程学院,上海200240

出　　处：《Transactions of Nonferrous Metals Society of China》2013年第1期289-293,共5页中国有色金属学报（英文版）

基　　金：Project(50874073) supported by the National Natural Science Foundation of China;Project(2011CB610405) supported by the National Basic Research Program of China;Project(2011M500074) supported by China Postdoctoral Science Foundation

摘　　要：A series of Co-Sn alloys with Sn content ranging from 12% to 32%（mole fraction） were undercooled to different degrees below the equilibrium liquidus temperature and the solidification behaviors were investigated by monitoring the temperature recalescence and examing the solidification microstructures.A boundary clearly exists,which separates the coupled growth zone from the decoupled growth zone of eutectic phases for the alloys with Sn content ranging from 14% to 31%（mole fraction）.The other Co-Sn alloys out of this content range are hard to be undercooled into the coupled growth zone in the experiment.It is found that the so-called non-reciprocal nucleation phenomenon does not happen in the solidification of undercooled Co-Sn off-eutectic alloys.将含12%-32%Sn(摩尔分数)的系列Co-Sn合金熔体过冷至平衡液相线以下不同温度进行凝固实验,通过监测快速凝固过程中的温度再辉与凝固组织分析不同过冷度下各合金的凝固行为进行研究。确定了Sn含量从14%到31%范围内Co-Sn合金凝固时共晶两相进行耦合生长和非耦合生长的分界线,在此成分范围之外的Co-Sn合金则很难被过冷至共晶共生区。在非共晶成分Co-Sn合金的深过冷凝固过程中不存在非互惠形核现象。

关 键 词：Co-Sn alloy UNDERCOOLING RECALESCENCE coupled growth zone SOLIDIFICATION microstructure evolution 

分 类 号：TG146.16[一般工业技术—材料科学与工程]