The subject of research is the surface layer of highly loaded parts, friction units of mining machines and equipment. The article presents a theoretical analysis of the factors that determine the ability of the material of the surface layer of parts to accumulate energy in the process of plastic deformation. It is suggested that the activation character of the accumulation of energy by metals. Based on the theory of diffusion, it was shown that the mobility of atoms, as well as the accumulated energy, are determined by the ratio of the test temperature to the melting temperature.
The technique for determining the temperature in the surface layer of the workpiece with a blade tool is considered, taking into account the volume heat source in the cutting zone, on the basis of which it is proposed to calculate the processing errors caused by the thermal action on the cutting tool and the workpiece being machined. When determining the thermal impact on the cutting edge of the tool, heat flows acting on the front and back surfaces are taken into account. When determining the thermal effect on the workpiece, the heat fluxes acting on deformation of the material when removing the chips and the back surface of the cutting tool are taken into account. The temperature in the cutting zone is determined by the summation of the temperature in the surface layer resulting from the plastic deformations of the material in the cutting zone, the friction of the chips against the front surface of the cutting tool and the friction of the back surface of the cutting tool against the treated surface. The peculiarity of the proposed method is that the physical and mechanical properties of the processed and tool materials (thermal diffusivity, ultimate thermal conductivity, specific volume heat capacity), processing regimes (cutting speed, feed and cutting depth), dimensions of the workpiece and cutting tool, geometry of the cutting tool (front and rear corners, radius at the top of the cutter in the plan, radius of rounding of the cutting tool, main and auxiliary corners in the plan). The calculations take into account the change in the intensity of volumetric heat fluxes in the cutting zone along their height.
