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This paper analyses the structure, hardness, and frictional wear resistance of surface layers formed on steels after hardfacing by means of the SSA arc method with self-shielded flux cored welding wire, with a content of carbon 5% and chromium 30% as well as boron alloying with the CO2 laser. S355J2 steel after being hardfaced with one up to three layers is characterized by the martensitic structure with chromium carbides and its surface hardness is 50–55HRC. In the weld deposit zone, with a thickness of up to approx. 2 mm, there is a constant distribution of hardness with the average value of 700 HV0.1, and then the hardness decreases to approx. 160 HV0.1 in the steel substrate. After hardfacing, the carbon content in S355J2 steel (0.23% wt.) increases to a similar content as in steel C90U in the initial state (0.96% wt.). After laser alloying with boron and after rapid cooling, C90U steel obtains distinctive paths with a zone structure and thickness reaching up to approx. 380 μm. In the remelted zone, there is a eutectic structure consisting of a mixture of iron borides and martensite with a hardness of approx. 1200–1800 HV0.1, and beneath it, there is heat affected zone with a martensitic-bainite structure with a hardness of approx. 700HV0.1. Hardfacing and laser heat treatment significantly decrease the frictional wear of the tested steels.

The main objective of this work is the numerical analysis of the strength and stiffness of an annular three-layer circular plate with variable mechanical properties of the core. The plates are subjected to bending. Numerical analysis of the deflection phenomenon is carried out under different support conditions of the plate. Furthermore, the influence of the material properties of the core (linear and non-linear model) on the shear stresses and deflecions is also investigated.