THE EFFECT OF ROLLING MODES ON THE RELATIVE BEARING LENGTH OF THE ELECTRIC SPARK SURFACE COATINGS

The study objective is to determine the effect of rolling modes on the formation of the relative bearing length of the surface of hard electric spark facing. The task to which the paper is devoted is to study the effect of modes of surface plastic deformation by rolling on the microgeometry of the surface: roughness and relative bearing length of the profile. Research methods. Theoretical analysis of literary sources on the topic of surface plastic deformation of part surfaces. Field experiments on rolling hard electric spark facings, followed by measuring the surface roughness, relative bearing length of the profile, and examining the microgeometry of the part surface using profilograms. The novelty of the work is in the fact that the modes of surface plastic deformation by rolling hard electric spark facings are developed. The practical significance is to ensure the possibility of rolling hard electric spark facings while reducing surface roughness and increasing the relative bearing length of the profile. Study results. As a result of the theoretical analysis, the method of surface plastic deformation was determined. Based on the results of measuring surface roughness, relative bearing length of the profile, microhardness and thickness of electric spark coatings after rolling, modes were determined that reduce roughness and increase the relative bearing length of the profile. Conclusions: in order to improve the performance of parts, it is necessary to form a certain microgeometry of the surface. Along with surface hardening by forming hard electric spark facing, it is necessary to ensure a low surface roughness and increase the relative bearing length of the profile. Special attention is paid to the study of modes of surface plastic deformation of hard electric spark coatings. An assumption is made about the mechanism of rolling hard electric spark coatings. The values of the surface microgeometry parameters and their photographs are presented. The values of surface roughness, relative bearing length of the surface profile, microhardness, and coating thickness are presented.