Columnar grain width control for SS316L via hatch spacing manipulation in laser powder bed fusion. Issue 3 (4th March 2023)

• Record Type: Journal Article
• Authors: Hu, Zhiheng; Gao, Shubo; Tai, Junfei; Qu, Shuo; Ding, Junhao; Song, Xu; Fan, Zheng
• Is Part Of: Materials research letters. Volume 11:Issue 3(2023)
• Page Start: 231
• Page End: 238
• Publication Date: 2023-03-04
• Subjects: Laser powder bed fusion -- hatch spacing -- columnar grain -- crystallographic texture -- stainless steel 316L; Materials science -- Research -- Periodicals; Biomedical materials -- Research -- Periodicals; Composite materials -- Research -- Periodicals; Biomedical materials -- Research; Composite materials -- Research; Materials science -- Research; Periodicals; 620.1105
• DOI: 10.1080/21663831.2022.2140018
• Languages: English
• ISSNs: 2166-3831

Abstract

Abstract : This study provides a quantitative way to tailor the grain structure in laser powder bed fusion (LPBF). Square-bottomed columnar grains (SCGs) were developed with a certain width roughly equal to the hatch spacing. The development of SCGs relied on different distinguishable regions, which were identified based on the differences in microstructural features between the melt-pool side and centreline. High lattice rotation accumulated at the melt-pool centreline, leading to grain boundaries forming at the centreline regions. The ultrasonic attenuation measurements and microhardness tests further validated the controllable properties. The findings indicated a novel approach to customise the material property. GRAPHICAL ABSTRACT: UF0001 IMPACT STATEMENT: A method to quantitatively control the columnar grain width in laser powder bed fusion was uncovered. The controllable properties were indicated, and the formation mechanism was revealed.