18Ni300模具钢激光选区熔化工艺优化及力学性能研究

优化激光选区熔化工艺, 制备18Ni300模具钢试样, 研究扫描速度和激光功率对模具钢力学性能的影响。结果表明, 当激光功率保持不变时, 随着扫描速度的增加, 18Ni300模具钢试样的相对密度和综合力学性能先增大后减小; 当扫描速度保持不变时, 随着激光功率的增加, 试样相对密度和综合力学性能逐渐增大; 能量密度在150 J·mm-3左右时, 试样的相对密度达到最高。激光选区熔化最优工艺参数是激光功率175W, 扫描速度400mm·s-1, 在此工艺参数下成形件的相对密度为99.58%, 抗拉强度、显微硬度和断后伸长率分别为1101 MPa、HV 348.4和6.44%。

Research on the process optimization of selective laser melting and the mechanical properties of 18Ni300 die steel

The 18 Ni300 die steels were prepared by the optimized selective laser melting, and the effects of scanning speed and laser power on the mechanical properties of 18 Ni300 die steels were studied.The results show that, when the laser power is constant, the relative density and the comprehensive mechanical properties of 18 Ni300 die steel specimen increase first and then decrease with the increase of scanning speed.When the scanning speed is constant, the relative density and the comprehensive mechanical properties increase with the increase of laser power.When the laser energy density is about 150 J·mm-3, the relative density of specimen is the highest.At the optimal scanning speed and laser power of 400 mm·s-1 and 175 W, the relative density, tensile strength, microhardness, and elongation of specimen are 99.58%, 1101 MPa, HV 348.4, and 6.44%, respectively.