Abstract
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 20–700ºC on LPBF 316L in as printed condition and after annealing for 5 h at 500–800ºC. 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 200ºC. 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 500ºC, but a decrease of yield strength was observed at temperatures above 600ºC likely due to a decrease in dislocation density via annealing.
| Original language | English |
|---|---|
| Article number | 101723 |
| Journal | Additive Manufacturing |
| Volume | 37 |
| DOIs | |
| State | Published - Jan 2021 |
Funding
The authors would like to thank, K. Carver, S. Hawkins, K. Hedrick, T. Lowe and V. Cox for their help with the experimental work. They also would like to acknowledge A. Shyam, Y. Lee and B. Pint for reviewing the manuscript. This research was sponsored by the U.S. Department of Energy , Office of Energy Efficiency and Renewable Energy , Vehicle Technologies Office , Propulsion Materials Program (USA).
Keywords
- 316L
- LPBF
- SLM
- Tensile properties
- Twinning
