Investigation of Mechanical Properties of Parts Fabricated with Gas- and Water-Atomized 304L Stainless Steel Powder in the Laser Powder Bed Fusion Process

• Published in: JOM (1989) 2022-03, Vol.74 (3), p.1088-1095
• Main Authors: Sehhat, M. Hossein, Sutton, Austin T., Hung, Chia-Hung, Newkirk, Joseph W., Leu, Ming C.
• Format: Article
• Language: English
• Subjects: Additive manufacturing; Atomizing; Austenitic stainless steels; Chemistry/Food Science; Digital cameras; Earth Sciences; Elongation; Engineering; Environment; Geometry; Investigations; Lasers; Mechanical properties; Metal powders; Morphology; Particle size; Particle size distribution; Physics; Powder beds; Production costs; Raw materials; Scanning electron microscopy; Solid Freeform Fabrication 2021; Stainless steel; Tensile strength; Tensile tests; Water
• ISSN: 1047-4838; 1543-1851
• DOI: 10.1007/s11837-021-05029-7

The use of gas-atomized powder as the feedstock material for the laser powder bed fusion (LPBF) process is common in the additive manufacturing (AM) community. Although gas-atomization produces powder with high sphericity, its relatively expensive production cost is a downside for application in AM processes. Water atomization of powder may overcome this limitation due to its low cost relative to the gas-atomization process. In this work, gas- and water-atomized 304L stainless steel powders were morphologically characterized through scanning electron microscopy (SEM). The water-atomized powder had a wider particle size distribution and exhibited less sphericity. Measuring powder flowability using the Revolution Powder Analyzer (RPA) indicated that the water-atomized powder had less flowability than the gas-atomized powder. Through examining the mechanical properties of LPBF fabricated parts using tensile tests, the gas-atomized powder had significantly higher yield tensile strength and elongation than the water-atomized powder; however, their ultimate tensile strengths were not significantly different.