Stress–Strain State of a High-Speed Steel Surface Layer at Plasma Surfacing

Using the finite-element method, the problem of thermoelastic stress distribution in a high-speed R2M9 steel coating on a 30KhGSA steel substrate has been solved. Stress distributions in the coating versus distance from the surface have been obtained. It has been found that normal component σ_yy of the stress tensor varies nonmonotonically along the rounding radius and monotonically along the central axis. It has also been shown that the von Mises stress intensity rises toward the coating boundary, as a result of which a minimum appears in the dependence of the microhardness on distance to the coating boundary. Stability analysis of carbide phase inclusions subjected to thermoelastic stresses has been carried out. It has turned out that inclusions 10 μm or greater in size are unstable if their thickness is about 1 μm or less.