【摘要】 本文成功地将显热容法和有限差分的三时间格式直接解法相结合,用以预示非纯净金属圆板受不同功率和不同光斑直径的激光束照射时溶化的形成与发展,与不纯铅板实验测试的结果符合良好。方法有效,而且简便,为激光加工领域的研究提供数学模拟计算的新途径。更多还原

【Abstract】 The phase change process in impure metallic plate irradiated by high power-density laser beam is studied experimentally and theoretically. The threetime-layer (TTL) scheme is useed to solve a two-dimensional transient heat conduction problem with phase change and the latent heat effect is approximated by an "apparent" or "equivalent" sensible heat capacity in the melting-point temperature range. Such a treatment meets, with success, to transform the complex heat transfer problem of solving boundary phase change to one dealing an ordinary transient heat conduction in solids with considerations of variable thermophysical properties including specific heat, thermal conductivity and surface absorptivity.更多还原