激光熔凝对4Cr5MoSiV模具钢组织及性能的影响

采用激光熔凝对4Cr5MoSiV模具钢进行了表面改性处理，研究了激光熔凝处理对模具钢组织和力学性能的影响．结果表明，材料经熔凝处理后，由表及里依次为熔凝层、淬火层、热影响区和基体．熔凝层由典型的柱状晶组成，熔凝层和淬火层之间存在一层极薄的等轴晶区；淬火层的晶粒发生细化和超细化．强化层厚度达1．1mm，平均硬度比基体提高26％，热影响区的厚度为0．3mm左右，强化层的耐磨性和耐腐蚀性显著提高．

Impact of Laser Melting on Structure and Properties of 4Cr5MoSiV Die Steel

The surface modification of 4Cr5MoSiV die steel was of laser melting processing on the microstructure and mechanical The results show that laser melt layer, laser quenching layer, produced by laser melting. The impacts properties of heat affected the die steel were studied. zone and substrate are in turns from the material＇s surface to inside. The melt layer is consisted of the typical columnar crystal,a very thin layer of equiaxial crystal grain zone is exists between the melt layer and the quenching layer, and grains refinement and ultrafine grains are appeared in the hardening layer. The thickness of hardening layer is 1. 1mm,the average hardness is increased by 26% comparing with the substrate,the thickness of the heat affected zone is about 0.3 mm. The wear resistance and corrosion resistance of the hardening layer are increased significantly.