Effects of manufacturing parameters, heat treatment, and machining on the physical and mechanical properties of 13Cr10Ni1.7Mo2Al0.4Mn0.4Si steel processed by laser powder bed fusion

This study investigates the effects of build orientations, heat treatment, and mechanical machining (as processing and post-processing factors) on the microstructure, quasi-static mechanical properties, strain hardening, notch toughness, and residual stress of additive manufactured 13Cr10Ni1.7Mo2Al0.4Mn0.4Si maraging stainless steel, known commercially as CX. The material investigated in this research was processed using the laser powder bed fusion (L-PBF) method as the additive manufacturing process. The results show that stainless steel CX had an anisotropic behavior under quasi-static tensile loads in its as-built condition. However, heat treatment significantly increased the strength of the material and eliminated the anisotropy in the strength levels. In addition, building orientation did not significantly affect the microstructure, hardness, and notch toughness. Further, retained austenite proved to have a role in determining the ductility and strain hardening of CX. Finally, the heat treatment utilized in this study proved to be effective in improving the mechanical properties employing shorter times and lower temperatures compared to the treatments used in other studies from the literature.

Automated summary

This study investigates the effects of build orientations, heat treatment, and mechanical machining on the microstructure, mechanical properties, and residual stress of additive manufactured CX stainless steel. The results show that heat treatment significantly improves the material's strength and eliminates anisotropy. Building orientation has minimal impact on the material's properties, while retained austenite plays a crucial role in its ductility and strain hardening.