电子束焊温度场的研究现状与发展趋势

电子束焊接作为一种高能束加工方法 ,在生产应用中具有重要地位。电子束焊温度场决定了焊接应力场和应变场 ,是影响焊接质量和生产率的主要因素。介绍了电子束焊温度场模型 ,在分析了点热源、线热源模型的基础上 ,指出点热源模型仍是研究焊接温度场的基础 ,同时介绍了其它几种考虑电子束小孔效应的温度场模型。讨论了计算温度场的热源模式 ,给出以高斯函数分布和双椭圆体能量密度分布的两种热源模式。列举了热物理参数、相变潜热、熔池流动等影响温度场的因素。认为基于解析解法的复杂性和计算机的飞速发展 ,数值解法将在温度场研究中发挥更加重要的作用

Survey and Development Trends of Electron Beam Welding Temperature Field

As a means of high-energy density beam processes, electron beam welding is used widely. Temperature field of electron beam welding, the main factor affecting the welding quality and productivity, determines stress and strain field, therefore research on temperature field is of practical significance. The models for temperature field were summarized. On the basis of analyzing point heat source and linear heat source, other models, considering the effects of keyhole of electron beam were introduced, and that the point source model is still thought as the basis of research on temperature field was pointed out. Heat source models for calculating temperature field were discussed, Gauss distributed source model and double ellipsoid heat source model were established. Other factors which affect temperature field, such as thermal properties, latent heat, welding pool fluid flow, were studied. Because the complexity of analytical solution and the rapid development of computer, numerical simulation will play a more important role in research of temperature field. Views about research on temperature field in the future are put forward.