FIELD: chemical and thermal treatment of samples. SUBSTANCE: process determining hardness of diffusion layer with due account of configuration effect deals with contacting planes of metal parts and includes chemical and thermal treatment of samples under various conditions, manufacture of microsection for metallurgical test sidewise to diffusion layer, determination of total thickness of diffusion layer in microsection, determination of microhardness of diffusion layer in thickness from surface to core and in core along bisectrix of angle and along normal to one of planes beyond configuration effect, averaging of values of microhardness along both directions, computation of relation of difference of averaged values of hardness to biggest one from average ones and selection of optimum condition of chemical and thermal treatment by its least value. EFFECT: improved efficiency of selection of optimum condition of chemical and thermal treatment. 1 dwg, 1 tbl
