Microstructure And High Temperature Tensile Properties Of 316l Fabricated By Laser Powder-Bed Fusion

316L stainless steel fabricated by laser powder-bed fusion (LPBF) has attracted significant attention due to a unique combination of strength and ductility at room temperature. Understanding of high temperature tensile properties of LPBF fabricated 316L is, however, limited. In the present investigation, tensile testing was conducted at 20-700 degrees C on LPBF 316L in as printed condition and after annealing for 5 h at 500-800 degrees C. Room temperature data confirmed the excellent ductility of the LPBF-processed 316L steel due to the cellular structure with high dislocation density. However, a significant decrease in ductility was observed at temperatures above 200 degrees C. These results are consistent with a change of deformation mechanisms observed in wrought 316L, with twinning playing a key role at room temperature. Microstructure characterization and tensile testing revealed that the cellular structure is stable up to 500 degrees C, but a decrease of yield strength was observed at temperatures above 600 degrees C likely due to a decrease in dislocation density via annealing.