Microstructure, texture, and anisotropic mechanical behavior of selective laser melted maraging stainless steels

In present research, the effect of building orientation on microstructure, texture and mechanical properties of a low carbon maraging steel processed by selective laser melting (SLM) technique is studied. The microstructural characterization and grain structure observations of the fabricated samples are conducted using electron mi-croscopies and electron backscatter diffraction. It is observed that by altering the building orientation from vertical to horizontal, the morphology of the grains changes from columnar-dendritic to equiaxed. In addition, a higher volume fraction of austenite is retained in the horizontal sample compared with the vertically printed sample due to a faster cooling rate, higher degree of micro-segregation, and smaller prior austenite grains. Consequently, a higher strength and better ductility are achieved in the horizontally printed sample. The Taylor factorshows that different obtained tensile properties are not related to the crystallographic texture but are affected by grain size, retained austenite, and stress concentration conditions.

Automated summary

The effect of building orientation on the microstructure, texture, and mechanical properties of a low carbon maraging steel processed by selective laser melting (SLM) technique is studied in this research. It is observed that changing the building orientation from vertical to horizontal alters the grain morphology and results in a higher volume fraction of austenite, leading to higher strength and better ductility in the horizontally printed sample. The crystallographic texture does not significantly affect the tensile properties, which are mainly influenced by grain size, retained austenite, and stress concentration conditions.