连续移动三维瞬态激光熔池温度场数值模拟

详细介绍了在ANSYS软件平台上,建立连续移动三维瞬态激光熔池温度场计算模型的方法,计算模型中考虑了材料表面温度对激光吸收率的影响及材料相变过程对激光熔池温度场的影响。系统分析了连续移动三维激光熔池温度场随时间的变化规律。通过该计算模型,可以掌握激光加工过程中连续移动激光熔池的加热和冷却规律。计算结果表明,当激光沿45#钢基板表面由一端向另一端沿直线扫描时,由于热传导的作用,激光熔池温度随时间增加而升高,同时连续移动熔池表面温度最高点不在激光束中心,而是稍稍偏后于激光束中心。在相同激光工艺参数下,计算熔池横截面尺寸与实验所测熔池横截面尺寸相吻合,表明所建立的连续移动熔池温度场计算模型是正确和可靠的。

Numerical Simulation for the Transient Temperature Field of 3D Moving Laser Molten Pool

In order to calculate the three-dimensional transient temperature field of the continuous moving laser molten pool, a numeric model is established basing on ANSYS software. In the established model, the influences of the surface temperature of material on laser absorptivity and phase change of material on temperature field of laser molten pool are taken into consideration. The analysis on the time-depended temperature field of laser molten pool is also conducted. During laser processing, the heating and cooling process of laser molten pool can be acquired by the numeric model. The calculated results show that when lasers scanning on the top surface of 45# steel base plate from one point to the another point along straight line, due to thermal conductivity, the temperature of laser molten pool increases with time increasing. The calculated result also indicates that the position of the highest temperature point on the laser molten pool surface is slightly lagged the position of the center point of the laser beam. Under the same laser process parameter conditions, the calculated result agrees with the experimental result, this indicates that the established numeric model is correct and reliable.