The influence of atmospheric environment on the forming quality of 316L components by laser powder bed fusion

Laser powder bed fusion (LPBF) technology is increasingly being applied to emergency rescue missions in high-altitude, island, and extremely cold environments. However, the complex atmospheric environment affects the quality consistency of LPBF-formed samples, which, to some extent, restricts the further development and application of LPBF technology in field manufacturing and emergency rescue. This study conducted on-site LPBF metal forming experiments in low-pressure, high-humidity, and extremely cold environments, exploring the impact of different atmospheric environments on the microstructure and mechanical properties of LPBF-formed 316L. The results show that different atmospheric environments, such as low pressure, high cold, and high humidity, have little effect on the density of LPBF 316L samples, with differences not exceeding 2.14%. The anisotropy differences in tensile properties in the X and Z directions of the deposited state are lower than those in the plain atmospheric environment. This paper provides a detailed explanation for the differences in tensile properties of X and Z direction samples and the abnormal reasons for the microstructure and properties of components formed in high humidity environments and proposes a series of improvement measures.