Correlation between surface texture and internal defects in laser powder-bed fusion additive manufacturing

• Published in: Scientific reports 2021-11, Vol.11 (1), p.22874-22874, Article 22874
• Main Authors: Yonehara, Makiko, Kato, Chika, Ikeshoji, Toshi-Taka, Takeshita, Koki, Kyogoku, Hideki
• Format: Article
• Language: English
• Subjects: 639/166; 639/301; Additive manufacturing; Control systems; Feedback; Humanities and Social Sciences; multidisciplinary; Powder; Science; Science (multidisciplinary); Statistical methods
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-021-02240-z

The availability of an in-situ monitoring and feedback control system during the implementation of metal additive manufacturing technology ensures that high-quality finished parts are manufactured. This study aims to investigate the correlation between the surface texture and internal defects or density of laser-beam powder-bed fusion (LB-PBF) parts. In this study, 120 cubic specimens were fabricated via application of the LB-PBF process to the IN 718 Ni alloy powder. The density and 35 areal surface-texture parameters of manufactured specimens were determined based on the ISO 25,178–2 standard. Using a statistical method, a strong correlation was observed between the areal surface-texture parameters and density or internal defects within specimens. In particular, the areal surface-texture parameters of reduced dale height, core height, root-mean-square height, and root-mean-square gradient demonstrate a strong correlation with specimen density. Therefore, in-situ monitoring of these areal surface-texture parameters can facilitate their use as control variables in the feedback system.