凝固速率对Si-Ta合金固液界面稳定性的影响  

Influence of Solidification Rate on Solid-liquid Interface of Si-Ta Alloy

作　　者：崔春娟[1,2] 张军[2] 吴昆[1] 邹德宁[1] 刘林[2] 傅恒志[2] 

机构地区：[1]西安建筑科技大学冶金工程学院,西安710055 [2]西北工业大学凝固技术国家重点实验室,西安710072

出　　处：《材料工程》2012年第8期60-64,共5页Journal of Materials Engineering

基　　金：国家自然科学基金资助项目(50102004);高等学校博士学科点专项科研基金新教师基金资助(20096120120017);陕西省自然科学专项研究基金资助(2012JQ6004);陕西省教育厅专项科研基金(12JK0425);西安建筑科技大学科技计划资助项目(人才科技基金RC0907)(基础研究基金JC1109)

摘　　要：以Si-Ta合金为研究对象,采用零功率法研究凝固速率对定向凝固固液界面稳定性的影响。结果表明:当凝固速率在0.3～9.0mm/min范围内,随着凝固速率的增大,固液界面经历了平界面→浅胞状界面→锯齿状界面→浅胞状界面→平界面的演化规律。在较低的凝固速率范围之内,实验结果与理论计算基本吻合。然而,在较高凝固速率时,实验结果与理论计算出现偏差,这是由于热力学和动力学均发生变化,使得在凝固速率V=5.0mm/min时固液界面就已经达到了稳定的平界面。The influence of solidification rate on the solid-liquid interface of $i-Ta alloy was studied by the zero power method. The results show that the solid-liquid interface morphology has the following evolution processing, planar interface-shallow cell interface-cell interface shallow cell interface- planar interface when the solidification rate varies from 0.3mm/rain to 9.0mm/rain. At the lower solidification rates, the experiment results can be consistent with Jackson-Hunt theory well. However, there is a deviation between the theory calculation and the experiment at the higher solidification rates. This is caused by the change of the thermodynamics and kinetics, and the solid-liquid interface can get to planar interface at the solidification rate Vz 5.0mm/min.

关 键 词：定向凝固 电子束悬浮区熔 凝固速率 固液界面 

分 类 号：TG244[金属学及工艺—铸造] O782[理学—晶体学]