籽晶法生长高温合金单晶凝固界面研究  

Solidification Interface in Growth of Single Crystal Superalloys by Seeding Technique

作　　者：赵乃仁[1] 李金国[2] 刘金来[2] 王志辉[2] 金涛[2] 孙晓峰[2] 管恒荣[2] 杨洪才[1] 胡壮麒[1] 

机构地区：[1]东北大学,沈阳110004 [2]中国科学院金属研究所,沈阳110016

出　　处：《材料工程》2007年第11期24-27,共4页Journal of Materials Engineering

摘　　要：研究了籽晶法生长单晶高温合金中固液界面的演变规律。实验结果表明:在籽晶法生长高温合金单晶的起始过程中,凝固系统经非稳态自组织过程达到稳态生长,凝固界面经历了由平界面—胞状界面—枝晶界面的转化过程,胞枝晶间距根据凝固参数及初始形态自行调整,其调整模式主要有竞争淘汰、尖端开裂和高次分枝三种。在生长起始端存在着籽晶与单晶的融合区,融合区的成分取决于籽晶成分和单晶成分。The evolution of solid/liquid interface during single crystal superalloy growth by seeding technique was investigated.The experiment results shows that the single crystal superalloy growth started from the top of seeds and the microstructure underwent the transformation from the unsteady self-organized to stable state.Solid/liquid interface changed from planar to cellular,then to dendrite.Primary arm spacing of cellular and dendrite crystal was modified by solidification parameters and initial morphology.Three types of adjusted model including competition selection,tip split and high order branching of dendrite can be identified.Fusion zone occurred between seeds and single crystal in starter growth.The composition of mushy zone depended on the chemical composition of seeds and the single crystal superalloy.

关 键 词：单晶高温合金 晶体生长 籽晶 固液界面 

分 类 号：TG132.32[一般工业技术—材料科学与工程]