316L不锈钢的激光选区熔化多道成形数值模拟研究

Numerical Simulation of Multi-pass Laser Selective Melting Forming of 316L Stainless Steel

通过对FLOW-3D软件的二次开发,实现了三维多道次的选区激光熔化(SLM)过程的数值模拟。对过程中熔池的速度场、温度场和形貌特征进行了分析,并与有限元方法和光滑粒子流体动力学方法的模拟结果进行了对比。对不同激光功率对熔池深度和宽度的影响进行了研究。结果表明,经过二次开发的FLOW-3D软件能精确模拟SLM过程中温度场;马兰戈尼对流对SLM过程中熔池形貌的形成有重要作用,并且熔池的长度与宽度随着激光功率的增大而增大。

Through the secondary development of the Flow-3 D software, the numerical simulation of the three-dimensional multi-pass selective laser melting(SLM) process was realized. The velocity field, temperature field and morphological characteristics of the molten pool were analyzed and compared with the simulation results of the finite element method and the smooth particle hydrodynamics method. The effects of different laser power on the depth and width of the molten pool were also investigated. The results indicate that the simulation of temperature field in the SLM process by secondary-developed Flow-3 D software present accurate. Marangoni convection plays an important role in the formation of the molten pool morphology during the SLM process, and the length and width of the molten pool is increased with laser power increase.