2021 №05 (02) DOI of Article
2021 №05 (04)

Automatic Welding 2021 #05
Avtomaticheskaya Svarka (Automatic Welding), #5, 2021, pp. 21-27

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

S.V. Adjamskiy1, G.A. Kononenko2, R.V. Podolskyi2

1LLC «Additive Laser Technology of Ukraine». 144 Rybinska Str., 49000, Dnipro, Ukraine. E-mail: info@alt-print.com
2Institute of Ferrous Metallurgy. Z.I. Nekrasova National Academy of Sciences of Ukraine. 1 Academician Starodubov Sq., 49000, Dnipro, Ukraine. E-mail: office.isi@nas.gov.ua

Selective laser melting (SLM) is one of the modern methods of additive manufacturing, which allows creating high-density parts with unique geometry from metal powder. To increase 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 of large tracks will increase its 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 focal spot of the laser. The specimens made at different focal spot diameters using the same laser power were examined. Based on the results of the analysis of technological parameters of the process it was established that to increase the efficiency of SLM-process the printing of the main body of a product can be performed at an increased focal spot diameter, and to provide a high surface quality. According to the redistribution of energy along the crosssection 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 Fig.
Keywords: selective laser melting, technological factors, quality system, AISI 316L, specific linear energy



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