双区加热定向凝固液相温度梯度研究

A Study of Temperature Gradient in Liquid Phase for Double-zone Heat Directional Solidification

在分析双区加热定向凝固热流的基础上推导出了液相中温度梯度（ＧＬ）的关系式，提出了提高ＧＬ的途径。结果表明：在双区加热时采用液体金属冷却在结晶生长速度较大时仍可获得很高的ＧＬ；当辐射挡板的厚度为３０ｍｍ，双区加热上下区的功率比为１∶２时，定向凝固温度较高，并可以进一步提高ＧＬ。

The formula of temperature gradient in liquid phase was duduced on the basis of analysis of heat flow for dotlble-zone heat directional solidification the way of enhancing temperature gradient was put forward. Results indicated that very high temperature gradient can be still obtained when growth rate is faster using liquid metal cooling in double-zone heat.Directional temperature is higber and temperature gradient can be raised further when thickness of radiation baffle is 30mm and power ratio of above ic below zone is 1:2