Experimental characterization of Inconel 625 powder stream and single track deposited on SS400 steel by direct laser metal deposition
41 viewsDOI:
https://doi.org/10.54939/1859-1043.j.mst.113.2026.168-175Keywords:
Direct laser metal deposition; Inconel 625; Powder stream characterization; Coaxial nozzle; Single track; Microstructure and microhardnessAbstract
Directed laser metal deposition (DLMD) offers significant potential for producing high-performance coatings and functional components, yet the effect of powder feed rate on coaxial powder stream stability and its correlation with single-track deposition quality remains insufficiently investigated. This study characterizes the Inconel 625 powder stream using light-sheet imaging and grayscale intensity analysis at feed rates of 5–30 g/min. The powder stream consistently converged at approximately 9 mm below the nozzle exit, independent of feed rate, ensuring stable alignment with the laser beam without adjusting the stand-off distance. The transverse profiles exhibited a Gaussian-like distribution. Based on these findings, single-track deposition on SS400 steel produced stable geometry, a fine cellular-to-columnar dendritic microstructure (primary dendrite arm spacing of 2.2–2.3 μm), uniform microhardness of 206.7–209.5 HV (about 25% higher than the substrate), and no porosity, lack-of-fusion, or solidification cracks. These results establish a direct link between powder stream characteristics and deposition quality, providing practical guidelines for robust DLMD processing of Inconel 625 on carbon steel substrates.
References
[1]. G. P. Dinda et al., “Laser aided direct metal deposition of Inconel 625 superalloy: Microstructural evolution and thermal stability”, Mater. Sci. Eng. A, Vol. 509, pp. 98–104, (2009). DOI: https://doi.org/10.1016/j.msea.2009.01.009
[2]. J. Cheng et al., “An overview of laser metal deposition for cladding: Defect formation mechanisms, defect suppression methods and performance improvements of laser-cladded layers”, Materials, Vol. 15, No. 16, p. 5522, (2022). DOI: https://doi.org/10.3390/ma15165522
[3]. Tran Van Cuong et al., “Study on the effect of halloysite nanotubes on the adhesion and corrosion protection of epoxy coatings on carbon steel”, J. Mil. Sci. Technol., No. IMBE, pp. 179–185, (2025). DOI: https://doi.org/10.54939/1859-1043.j.mst.IMBE.2025.179-185
[4]. Nguyen Van Son et al., “Investigation of environment parameters and metal corrosion rate n atmospheric enviroment at Phan Thiet”, J. Mil. Sci. Technol., No. 84, pp. 80–85, (2022).
[5]. Y. Ma et al., “The atmospheric corrosion kinetics of low carbon steel in a tropical marine environment”, Corros. Sci., Vol. 52, pp. 1796–1800, (2010). DOI: 10.1016/j.corsci.2010.01.022. DOI: https://doi.org/10.1016/j.corsci.2010.01.022
[6]. R. E. Melchers, “Long-term corrosion of cast irons and steel in marine and atmospheric environments”, Corros. Sci., Vol. 68, pp. 186–194, (2013). DOI: 10.1016/j.corsci.2012.11.014. DOI: https://doi.org/10.1016/j.corsci.2012.11.014
[7]. F. Zafar et al., “A review on direct laser deposition of Inconel 625 and Inconel 625-based composites-challenges and prospects”, Metals, Vol. 13, No. 4, p. 787, (2023). DOI: 10.3390/met13040787. DOI: https://doi.org/10.3390/met13040787
[8]. L. Li et al., “Numerical study on powder stream characteristics of coaxial laser metal deposition nozzle”, Crystals, Vol. 11, No. 3, p. 282, (2021). DOI: 10.3390/cryst11030282. DOI: https://doi.org/10.3390/cryst11030282
[9]. X. Guan et al., “Numerical modeling of coaxial powder stream in laser-powder-based directed energy deposition process”, Addit. Manuf., Vol. 34, p. 101226, (2020). DOI: 10.1016/j.addma.2020.101226. DOI: https://doi.org/10.1016/j.addma.2020.101226
[10]. K. Wang et al., “Powder stream performance of a novel annular laser direct metal deposition with inside-laser coaxial powder feeding nozzle: Simulation and experimental perspectives”, Opt. Laser Technol., Vol. 175, p. 110723, (2024). DOI: 10.1016/j.optlastec.2024.110723. DOI: https://doi.org/10.1016/j.optlastec.2024.110723
[11]. P. Balu et al., “Parametric study on a coaxial multi-material powder flow in laser-based powder deposition process”, J. Mater. Process. Technol., Vol. 212, pp. 1598–1610, (2012). DOI: https://doi.org/10.1016/j.jmatprotec.2012.02.020
[12]. N. Tamanna et al., “Progress in numerical simulation of the laser cladding process”, Opt. Lasers Eng., Vol. 122, pp. 151–163, (2019). DOI: 10.1016/j.optlaseng.2019.05.026. DOI: https://doi.org/10.1016/j.optlaseng.2019.05.026
[13]. J. Lin, “Numerical simulation of the focused powder streams in coaxial laser cladding”, J. Mater. Process. Technol., Vol. 105, pp. 17–23, (2000). DOI: 10.1016/S0924-0136(00)00584-7. DOI: https://doi.org/10.1016/S0924-0136(00)00584-7
[14]. N. T. Hung et al., “Research on the microstructure and mechanical properties of high-entropy alloys manufactured using 3D printing technology”, J. Mil. Sci. Technol., Vol. 98, pp. 164–170, (2024).
