Abstract
Metal powders with uniformly dispersed nanoparticles, suitable shape, and size for additive manufacturing (AM) processes are highly demanded. However, it is difficult to manufacture metal matrix nanocomposite powders (MMNCs) with uniform dispersion of nanoparticles, optimized shape, and size. This study used high-energy ball milling to disperse NbC nanoparticles with an average length of 400 nm (ex-situ reinforcement) in a Stainless Steel (SS) 304 L matrix. In detail, SS304L-5wt% NbC powders were ball-milled from 4 to 10 h. The results showed that the milled powder particles experienced significant cold-welding during the milling time of 4–6 h, with a wide size distribution. NbC distribution in the SS304L matrix was gradually improved as ball milling time increased, with a uniform dispersion achieved after 8 h of ball milling. The morphology of the 8-h ball-milled nanocomposite powders was approximately 92% spherical. The uniform dispersion of NbC particles was achieved in laser-melted matrix, which was scanned at laser power 200 W and a scan speed of 670 mm/s. The microstructure of the single-layer melted nanocomposite comprised of fine grains (8–17 µm) with NbC particles homogenously dispersed in the SS304L grains. The measured average micro-hardness of SS304L-5 wt% NbC increased by 63% compared with the SS304L powder ball-milled for 8 h, indicating that dispersed NbC particles in the SS304L matrix significantly improved the mechanical properties of the ball-milled powders. This research provides a promising way to produce SS304L-NbC nanocomposite powder for powder bed fusion of metals using a laser beam.
Recommended Citation
K. H. Solangi et al., "Powder Bed Fusion of Stainless Steel 304L-NbC Nanocomposite Produced by Ball Milling Method using a Laser Beam," Progress in Additive Manufacturing, vol. 10, no. 11, pp. 9291 - 9304, Springer, Nov 2025.
The definitive version is available at https://doi.org/10.1007/s40964-025-01248-5
Department(s)
Mechanical and Aerospace Engineering
Keywords and Phrases
Ball milling; Metal matrix nanocomposite (MMNC); Powder bed fusion of metals using a laser beam (PBF-LB/M); Powder characterization; Stainless steel 304L
International Standard Serial Number (ISSN)
2363-9520; 2363-9512
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2025 Springer, All rights reserved.
Publication Date
01 Nov 2025
Comments
U.S. Department of Energy, Grant DE-NA0002839