微型器件选区激光熔化成形温度场的有限元分析

Finite Element Analysis on Temperature Field of Micro Device Forming by Selective Laser Melting

为选择合适的工艺参数实现微型器件的选区激光熔化直接成形,利用ANSYS有限元软件对成形过程的温度场进行了分析。结果表明,温度场的形貌大致呈椭圆形,熔池位置滞后于激光光斑位置,粉末层最高温度、熔池最大宽度和深度均随着扫描速度的增加而减小、随着激光功率的增加而增大。根据分析结果选择合适的工艺参数,当光斑直径为50μm、粉末层厚为30μm、激光功率为200W、扫描速度为800mm/s和扫描间距为100μm时,成形的效果最好,制备出了具有较高精度和物理性能的微型钻头。

The temperature field of forming process is analyzed by the finite element analysis software ANSYS,in order that the suitable processparameters are chosen for directly forming of micro devices with selective laser melting. The results show that the temperature fieldisoval-shaped,and the location of the molten pool lags behind the laser spot. The maximum temperature of the powder layer,the maximum width and depth of the molten pool are decreased with the increase of the laser scanning speed,while increased with the increase of the laser power. A set of suitable process parametersis obtained： the laser power is 200 W,the scanning speed is 800 mm/s,the scanning pitch is 100μm,the diameter of laser spot is50μm and the thickness of powder layer is 30μm. Based on the work,a microdrill with a high accuracy and physical properties is formed successfully.