In the process of laser metal powder deposition using an annular laser beam (ALB), shadowing of the ALB occurs due to the powder being fed into the center of the beam. This results in a local reduction in energy density, which can lead to asymmetric deposition shapes, variations in dilution, and uneven metallurgical bonding between the clad and the substrate. In the theoretical part, we present the basics of additive manufacturing technologies and the system utilizing an annular laser beam. In the experimental part, we first describe the experiments conducted to determine the process parameters where the impact of shadowing is observed. For selected parameters, we then analyze the impact of shadowing on the deposition of powder (AISI 316L) onto the substrate (AISI 304). We found that shadowing can cause an asymmetric shape, an increase in the wetting angle, and in some cases, reduced dilution on the shadowed side, which can lead to poorer deposition quality
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