OBRABOTKAMETALLOV MATERIAL SCIENCE Vol. 26 No. 2 2024 The monolayers microhardness is slightly higher than the one of the previously obtained tracks and amounts to 487 ± 15 HV, while the microhardness value of the monolayer does not depend on the deposition mode (Fig. 7). This result is likely due to the fact that during the laser deposition of multiple tracks, due to the re-heating of the already surfaced material, aging processes occur, i.e., the breakdown of supersaturated solid solutions, resulting in an increase of alloy microhardness. The modes providing the most uniform layer and the absence of macrodefects were selected to create bulk specimens (Table 5). a b c Fig. 6. Effect of the distance between tracks on the relative height difference (∆h/h) (a), monolayer height (h) (b), ratio of penetration depth to monolayer height (p/h) depending on laser power (c) (green area – area of acceptable values) Fig. 7. Dependence of microhardness of monolayers and bulk specimens on laser power Ta b l e 5 Modes selected according to the structure of monolayers Laser power P, W 700 700 800 800 900 1.000 1.100 Scanning speed V, mm/min 800 800 1.000 1.000 1.000 1.000 1.000 Distance between tracks 0.5L 0.7L 0.5L 0.7L 0.7L 0.7L 0.7L
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