工艺参数对选区激光熔化CuCrZr合金单道次熔道特性的影响

Effect of Process Parameters on the Single-pass Characteristics of CuCrZr Alloy Melted by a Selective Laser

选区激光熔化(selective laser melting, SLM)制备合金过程中,材料经历了快速熔化和凝固,工艺参数选择不当可能导致熔道出现缺陷。本文通过微观尺度下的数值模拟和实验证实,旨在研究不同工艺参数下单层单道次SLM过程中CuCrZr合金的熔道特征。模拟与实验结果表明,在单道次打印过程中,激光功率和扫描速率的变化会对熔池形貌产生影响。当激光功率从250 W增加到450 W时,熔道宽度逐渐增加至124μm,并且熔道表面出现波纹形貌。而当扫描速率从0.4 m/s增加到0.8 m/s时,熔道宽度逐渐减小,波纹形貌消失。当激光功率为250 W,扫描速率为0.8 m/s时,激光能量输入不足,导致熔道出现球化现象。然而,随着激光功率的增加,球化现象消失,金属粉末颗粒在熔道边缘局部熔化,导致单道不平直现象的出现。

In the process of selective laser melting(SLM),materials undergo rapid melting and solidification,and improper selection of process parameters may lead to defects in the fuse.In this study,the fusible characteristics of CuCrZr alloy in a single-layer single-pass SLM process with different process parameters were studied by numerical simulation and experimental verification at the microscale.The results show that the morphology of the molten pool is affected by the change in laser power and scanning rate during single-pass printing.When the laser power increases from 250 W to 450 W,the width of the fuse gradually increases to 124μm,and ripples appear on the surface of the fuse.When the scanning rate increases from 0.4 m/s to 0.8 m/s,the width of the fuse gradually decreases,and the ripple morphology disappears.When the laser power is 250 W and the scanning rate is 0.8 m/s,the laser energy input is insufficient,resulting in spheroidization of the fuse.However,with increasing laser power,the spheroidization phenomenon disappears,and the metal powder particles locally melt at the edge of the fuse,resulting in the occurrence of single channel irregularity.