摘要
由于液态合金与铸型界面间的相互作用,液态的自由表面与铸型表面接触处形成弯月形的空间曲面。基于此,提出了一种测量液相线温度下表面张力的方法。对于具有一定宽度结晶范围的高温合金,对定向凝固过程分析发现,凝固后的自由表面弯月形曲面在能够较为精确反映液相线温度下液态合金的弯月形曲面。在常温下测量弯月形曲面,根据Young-Laplace关系计算,就可以得到该合金液相线温度下的表面张力。通过对单晶高温合金DD6进行实验,得到液相线温度下DD6的表面张力约为1.34J·m-2。
Owing to interface inieraction between liquid metal and casting mould wall, the surface characteristic of meniscus of liquid comes into being. So a method to measure the surface tension at iiquidus temperature was proposed. It is concluded that during the slow directional solidification, the meniscus surface of liquid metal at liquidus temperature can keep its morphology at room temperature for a superalloy. Surface tension at liquidus temperature can be calculated by using Young-Laplace formation after measuring the meniscus surface at room temperature. By the method, the surface tension of the single crystal superalloy at liquidus temperature, DD6, can be obtained, which is 1.34 J·m^-2.
出处
《热加工工艺》
CSCD
北大核心
2009年第23期57-60,共4页
Hot Working Technology
关键词
表面张力
定向凝固
高温合金
surface tension
directional solidification
superalloy
