METHOD OF CASE HARDENING PARTS Russian patent published in 1994 - IPC

FIELD: mechanical engineering. SUBSTANCE: part has regular macrotexture applied to its surface with a coating following. To achieve macrotexturing the part is consecutively undercut to the depth equal to S the surface layer of the part material having a pitch h sin(ϕ) sin(ϕ₁). The undercut layer is bent to take the position defined by the angle ϕ₁ the composite coating layers make with the starting surface of the part. The formed rib is simultaneously hardened its side surfaces being next impregnated. In the above-given expressions h - thickness of coating, ϕ - angle of undercutting the surface layer equaling arcsin (sin (ϕ₁-b) S). EFFECT: higher reliability and durability of the parts.