Studies on Young's modulus and microhardness of laser fused surfaces: Sm-Co on the stainless steel and Sm-Fe on the duralumin substrates have shown the heterogeneity of depth properties with local maximum in areas not containing micro cracks. Maximum hardening was obtained for Sm-Fe system. Found that hardening of laser fused layers and the increase their resistance to compression and tension on the stainless steel substrate is associated with the formation of multicomponent alloys (Fe17.8Ni25.6Cr5.6C11.0Sm32.1and Fe64.3Ni1.9Cr16.6C5.5Sm8.4) due to the diffusion of atoms of the substrate and depends on the availability of the micro crack’s grid of and the alloy microstructure. The high Al diffusion speed from duralumin substrate in the fused layer, formed from Sm powder, and then from Fe powder, led to the segregation of Al on the surface, formation of triple oxide (AlSmO3) with maximum microhardness and Young's modulus. Further decrease of both parameters is associated with the formation of micro cracks, but a local maximum connects with strong decreasing of microcrack’s density and formation of Al2Sm layer.
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