The Paton Welding Journal, 2021, №05



2021 №05 (02)

DOI of Article 10.37434/tpwj2021.05.03

2021 №05 (04)

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The Paton Welding Journal, 2021, #5, 18-23 pages

Improving the efficiency of the SLM-process by adjusting the focal spot diameter of the laser beam

S.V. Adjamskyi¹, G.A. Kononenko² and R.V. Podolskyi²

¹LLC «Additive Laser Technology of Ukraine» 144 Rybinska Str., 49000, Dnipro, Ukraine. E-mail: info@alt-print.com
²Z.I. Nekrasov Iron and Steel Institute of the NAS of Ukraine 1 Academician Starodubov Sq., 49000, Dnipro, Ukraine. E-mail: office.isi@nas.gov.ua

Abstract
Selective laser melting (SLM) is one of the modern methods of additive manufacturing, which allows creating high-density parts with a unique geometry from metal powder. To improve the efficiency of the SLM process, it is desirable to increase the width of the melt pool, as this will increase the distance between the laser passes and a larger volume will be built in a shorter period of time. However, the formation of the outer surface by large tracks will result in its higher roughness, which can significantly reduce the overall reliability of a product. To improve the surface quality, it is necessary to reduce the size of the melt pools, for example, by reducing the diameter of the laser focal spot. The samples were examined produced at different focal spot diameters using the same laser power. Based on the results of the analysis of technological parameters of the process, it was established that to increase the efficiency of SLM-process, printing of the main body of a product can be performed at an increased laser beam focal spot diameter, and to provide a high surface quality, printing of a contour part (shell) should be more performed using a more localized focal spot. According to the redistribution of power along the cross- section of the beam, a change in the configuration of the melt pool, and accordingly the track occurs. It was established that in order to avoid the formation of deep remelting due to a high concentration of energy in the center of the beam, it is necessary to reduce the laser power. 29 Ref., 6 Figures.
Keywords: selective laser melting, technological factors, quality system, AISI 316L, specific linear energy

Received 14.04.2021

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Suggested Citation

S.V. Adjamskyi, G.A. Kononenko and R.V. Podolskyi (2021) Improving the efficiency of the SLM-process by adjusting the focal spot diameter of the laser beam. The Paton Welding J., 05, 18-23.

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