电子束退火法制备MgB_2薄膜的温度场模拟

Temperature field simulation of MgB_2 thin film annealed by electron beam

利用ANSYS软件模拟电子束退火MgB_2薄膜过程的温度场分布,退火样品与样品台之间的接触热阻对退火温度影响很大,且此接触热阻会随退火参数(电子束能量和退火时间)发生变化,这给模拟工作带来很大困难。本文先通过热阻串联对样品进行等效简化,再利用热传导近似计算把接触热阻的效应等效在样品模型中,并将接触热阻随退火参数的变化转化为电子束能量转化效率的变化,得到修正后的热源模型,仿真所得温度值与实测温度值基本相符,这为电子束退火制备薄膜材料的研究提供了温度参考。

Temperature field distribution of MgB2 thin film annealed by electron beam was simulated by ANSYS software. The contact thermal resistance between the sample and the sample stage had great influence on the annealing temperature, and it changed with the power of electron beam and annealing duration, which brought great difficulty to the simulation work. In this paper, firstly the sample was simplified through the equivalent thermal resistance and then the contact thermal resistance were equivalent to the physical model based on the heat transfer computation, and the change of the contact thermal resistance in the annealing process was converted innovatively to the change of the energy conversion efficiency. So the revised model of electron beam heat source was obtained. The temperature of simulation is mainly coincident with the measured temperature. This work provides a temperature reference for the research of electron beam annealing to prepare thin film materials.