PHYSICO-TECHNOLOGICAL FOUNDATIONS OF INCREASING THE DURABILITY OF DIE TOOLS BY HARDENING WITH HIGH-ENERGY FLOWS

The issues of the formation of equilibrium conditions in ordered dislocation structures obtained by the action of highly concentrated electric energy fluxes and an informal (longitudinal-torsional) ultrasonic field on a conductive substrate material are viewed. The effect of solid surface films on deformation and fracture, being used as barriers and capable of suppressing the occurrence of new dislocations during metal deformation processes, is shown. The factors that determine to a greater extent the effectiveness of the film in creating a barrier for dislocations have been identified. A simplified analytical model of the interaction of a single dislocation with the layers obtained by the combined hardening method and the conditions for the equilibrium of dislocations in a film of a given thickness are proposed. The results of experimental studies of a hardened layer formed by anodizing with tungsten and copper on grade 20 steel are presented. They have shown that an increase in product strength occurs under conditions when the shear modulus of the base crystal is less than the shear modulus of the sawn layer, and the action force from this layer tends to push the dislocation away from the phase interface. As a result of the study of electroacoustic spraying effect on the quality and wear resistance of the surface of a die tool, it was confirmed that electroacoustic spraying, realizing a complex effect on metal, improves the quality of tool edges and their strength characteristics, forming a predictable organization of the surface layer structure; a "double barrier" created during electroacoustic spraying on the surface, preventing the release of dislocations on the surface is the main factor in increasing the strength properties of the tool. It was found that the coating applied by the electroacoustic method increases the service life by 1,5 − 2 times if compared to samples where surface was not treated by the above-mentioned method.

dislocation structures, high-energy flows, reinforced layer, electroacoustic spraying, quality, wear resistance, form tool