{"title":"Effects of scan rotation angle and build orientation on mechanical anisotropy in additive manufacturing 316L stainless steel","authors":"","doi":"10.1016/j.jmapro.2024.08.043","DOIUrl":null,"url":null,"abstract":"<div><p>The scan rotation angle (SRA) and build orientation (BO) in the laser powder bed fusion (LPBF) process create unique microstructural features that induce mechanical anisotropy in 316L-stainless steel (SS). To thoroughly investigate their individual and collaborative effects on anisotropy, 316L-SS samples were fabricated with SRAs between adjacent layers (abbreviated as R) of R0 (0°), R45 (45°), R67 (67°), and R90 (90°), and BOs in the XY plane ranging from XY0 to XY90 at intervals of 15°. Tensile testing results revealed that XY0–R67 samples exhibited the highest yield strength (YS), ultimate tensile strength (UTS), and ductility among all samples, while the lowest YS, UTS, and ductility were observed for XY0–R0 samples. Characterization at different length scales was performed to investigate the underlying reasons contributing to mechanical anisotropy. X-ray diffraction (XRD) results indicated that all samples possessed single-phase austenitic structures with varying dislocation densities. The dislocation density had the highest contribution to the YS of LPBF-built 316L-SS in the sequence of XY0–R67 > XY0–R90 > XY0–R45 > XY0–R0. The higher dislocation density in XY0–R67 samples stemmed from the larger residual stresses associated with the higher lattice strains due to the more complex thermal histories and higher cooling rates compared to other cases. A similar phenomenon was also observed for the XY45 BO, which exhibited higher YS due to higher dislocation densities compared to other orientations, regardless of SRAs. Additionally, SRAs significantly influenced the evolution of crystallographic texture, which also affected the YS of LPBF-built 316L-SS.</p></div>","PeriodicalId":16148,"journal":{"name":"Journal of Manufacturing Processes","volume":null,"pages":null},"PeriodicalIF":6.1000,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Manufacturing Processes","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1526612524008752","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, MANUFACTURING","Score":null,"Total":0}
引用次数: 0
Abstract
The scan rotation angle (SRA) and build orientation (BO) in the laser powder bed fusion (LPBF) process create unique microstructural features that induce mechanical anisotropy in 316L-stainless steel (SS). To thoroughly investigate their individual and collaborative effects on anisotropy, 316L-SS samples were fabricated with SRAs between adjacent layers (abbreviated as R) of R0 (0°), R45 (45°), R67 (67°), and R90 (90°), and BOs in the XY plane ranging from XY0 to XY90 at intervals of 15°. Tensile testing results revealed that XY0–R67 samples exhibited the highest yield strength (YS), ultimate tensile strength (UTS), and ductility among all samples, while the lowest YS, UTS, and ductility were observed for XY0–R0 samples. Characterization at different length scales was performed to investigate the underlying reasons contributing to mechanical anisotropy. X-ray diffraction (XRD) results indicated that all samples possessed single-phase austenitic structures with varying dislocation densities. The dislocation density had the highest contribution to the YS of LPBF-built 316L-SS in the sequence of XY0–R67 > XY0–R90 > XY0–R45 > XY0–R0. The higher dislocation density in XY0–R67 samples stemmed from the larger residual stresses associated with the higher lattice strains due to the more complex thermal histories and higher cooling rates compared to other cases. A similar phenomenon was also observed for the XY45 BO, which exhibited higher YS due to higher dislocation densities compared to other orientations, regardless of SRAs. Additionally, SRAs significantly influenced the evolution of crystallographic texture, which also affected the YS of LPBF-built 316L-SS.
期刊介绍:
The aim of the Journal of Manufacturing Processes (JMP) is to exchange current and future directions of manufacturing processes research, development and implementation, and to publish archival scholarly literature with a view to advancing state-of-the-art manufacturing processes and encouraging innovation for developing new and efficient processes. The journal will also publish from other research communities for rapid communication of innovative new concepts. Special-topic issues on emerging technologies and invited papers will also be published.