ABSTRACT

Directed energy deposition (DED) shows outstanding advantages in manufacturing complex and functionally graded parts. This study systematically investigated the effect of laser incident energy on the densification, microstructure, texture evolution and mechanical properties of CrCoNi thin-walled parts manufactured by the DED. The results show that the <001>//BD crystallographic orientation is slightly enhanced with the increase in laser incident energy, and the yield strength shows a decreasing trend. Meanwhile, the anisotropy of yield strength and ultimate tensile strength did not change significantly with the increase of laser incident energy. In addition, there is a certain difference between the fracture morphology and microcrack characteristics in the building and scanning direction. These findings provide an important theoretical basis for the selection of DED process parameters.

摘要

定向能量沉积 (DED) 在制造复杂和功能分级的零件方面显示出突出的优势。本研究系统地研究了激光入射能量对 DED 制造的 CrCoNi 薄壁零件的致密化、微观结构、织构演变和机械性能的影响。结果表明，随着激光入射能量的增加，<001>//BD晶体取向略有增强，屈服强度呈下降趋势。同时，随着激光入射能量的增加，屈服强度和极限抗拉强度的各向异性没有明显变化。此外，在构建和扫描方向上，断裂形态和微裂纹特征存在一定差异。