PHYSICO-TECHNOLOGICAL ANALYSIS OF ELECTRO-SPARK MACHINING OF RECONDITIONED PARTS MADE OF STRUCTURAL AND TOOL STEELS

The reliability and durability of friction units in modern weapons and military equipment largely depend on the physical and mechanical properties of the materials of the parts and the quality of their surface treatment.One of the promising methods for improving the performance characteristics of weapons and military equipment is electrospark alloying (ESA), which allows the creation of hardened coatings with high wear resistance.The article deals with the physical processes occurring during ESA, particularly electrical erosion, polar material transfer, and structural and phase transformations of the surface layer.It is shown that using electrodes with nanostructured modifiers to form ultra-strong coatings with specified functional characteristics is promising.Further improvement of the design of installations for mechanized coating formation, which ensures process stability and high productivity, is significant.The process modes, electrode parameters, and their influence on the formation of coatings are analyzed.The formation mechanism of surface layers and features of their crystallization are presented.It was found that using ESA promotes the formation of white layers with a fine-grained structure, characterized by high mechanical properties and corrosion resistance.A further analysis of the technological parameters of ESA demonstrated a significant effect of the electrode material on the composition and characteristics of the obtained coatings.The influence of pulse discharge modes on the depth of penetration of alloying elements into the surface layer of the part was determined.It is shown that special attention should be paid to the influence of the gas environment of the interelectrode gap on the kinetics of the material transfer process.In practical terms, the research results demonstrate the effectiveness of using ESA for the restoration and strengthening of parts operating under difficult operating conditions, in particular in the friction units of the vehicle.The authors' experiments have confirmed the possibility of adjusting the microhardness and thickness of coatings by optimizing the processing modes and composition of the electrode material.As a result, it was concluded that electric spark alloying is an effective method of strengthening the surfaces of parts, ensuring their durability and operational reliability, and surpassing traditional technologies in several key parameters.