Abstract
This study investigated the microstructure, residual stress, and tensile properties of directed energy deposited stainless steel 316L (SS316L) under thermal annealing. Microstructure characterization shows the as-printed sample has laser-generated patterns where dendritic structure is observed at the edge of the patterns and cellular structure dominates the interior region. The thermal annealing at 983 and 1093°C effectively removes the dendritic/cellular structures. Synchrotron x-ray diffraction reveals that the as-printed SS316L exhibits compressive residual stress of − 197.4 MPa, which is greatly relieved to − 53.8 MPa after annealing at 1093°C. The room temperature tensile testing indicates that the yield strength and ultimate tensile strength drop from 378 MPa and 502 MPa in the as-printed sample to 258 MPa and 446 MPa in the annealed samples (1093°C), respectively. Our study provides insights into the relationship among microstructure, residual stress, and tensile properties of laser additive manufactured SS316L.
| Original language | English |
|---|---|
| Pages (from-to) | 4167-4177 |
| Number of pages | 11 |
| Journal | JOM |
| Volume | 72 |
| Issue number | 12 |
| DOIs | |
| Publication status | Published - Dec 2020 |
| Externally published | Yes |