长脉冲激光与连续激光对铝板热破坏仿真对比

Simulation Contrast of Thermal Damage on an Aluminum Plate Induced by Long-pulse Laser and CW Laser

为了研究长脉冲激光与连续激光对铝合金的热破坏损伤差异,本研究建立了基于ANSYS的长脉冲激光与连续激光分别辐照铝合金的计算模型,利用变化体热源技术和生死单元技术,计算了两种制式激光辐照下铝合金的温度场分布以及融池大小。仿真结果为:功率为500 W的连续激光对铝板辐照1秒后,铝板最高的温度只有173℃,并没有达到铝板的融化温度,所以铝板表面并不会出现融池。而能量为500 J的单个毫秒脉冲激光可产生深度为1.4 mm,最大直径为3.6 mm的熔池。得出了在相同能量下,长脉冲激光对铝合金的损伤效果比连续激光更好的结论。

This paper institutes a calculation model based on ANSYS to study the differences between the thermal damages of an aluminum alloy induced by a long-pulse laser and a CW laser. Utilizing the heat generation rates and death unit technologies, it calculates the temperature distributions and the melt pool sizes of the aluminum alloy at the two kinds of radiation. Eventually it is concluded that the thermal damage at the radiation of long-pulse laser is better than the CW laser with equal energy. The simulation results have been obtained as： It will not cause a melt pool at the surface of the aluminium plate because the highest temperature of the plate is 173℃ when radiated by a 500W-CW laser source after a second. However, a melt pool with 1.4 mm-depth and 3.6mm-maximum diameter will appear when the aluminium plate is radiated by a 500 J millisecond pulsed laser.Eventually a conclusion is got that the thermal damage at the radiation of long-pulse laser is better than the CW laser.