Tendency of the world‘s manufacturers to strengthen the surfaces of machine parts is caused by the necessity to protect from damage the materials and coatings subjected to wear. The latter are the composite electrochemical iron-boron carbide coatings (CEC), which are deposited from the electrolytes, i.e., suspensions that contain iron chloride (FeCl2 4H2O) – 500…600 kG/m3 and microparticles of boron carbide (B4C) with dispersivity of 1…40 m. The technological process of plating (TPP) (ironing) makes it possible to satisfy the requirements of ecological safety in absolute measure, ensures the inclusion of the disperse phase (DP) into the iron matrix up to 30 %, and allows an easy technical control by the composition of the coatings. The composition electrochemical coatings after their being electrodeposited are a mechanical mixture of metal-disperse phase, characterized, in condition of lubrication, by a high wear resistance, which exceeds that of ‗clean‘ iron coatings by an order of magnitude. That is why they are recommended to be used in extremely loaded junctions. The TPP mechanism can be explained by the following facts: the DP particles - a) in the friction couples accept the load from the counter body and distribute it into the matrix and in doing so they protect the matrix surface from the direct contact; b) they form and holdan oil ―pillow‖ by their protruding elements over the matrix surface, which decreases the friction coefficient; and c) they protect the matrix from scoring and seizure.  Alongside with the above advantages, the composition iron coatings have a number of significant disadvantages. In particular, the coatings have: 1) a very weak corrosion resistance in the open air, measured by the tens of minutes, during which the entire surface is covered with a layer of rust, loosing its outward appearance and market quality; 2) absolutely low cohesive strength with carbon hardened and alloyed steels, which reduces their region of application both in machine building and maintenance service. It is worth noting that the cohesive strength is the most important factor for all galvanic coatings, and it affects the perspective of their application; 3) insufficiently high degree of wear resistance in utilization with abrasive materials.  Heat treatment with the high frequency current (HFC), formed in the composition layer (Fe -B4C) new strength structures and joined them with the metal substrate. The study of the modification process was performed at temperatures of 950…1150ºС withholding from 0 to 100 s, after which they were cooled in the air or quenched in water or oil. At high temperatures, the transition and annihilation of defects occur in the crystalline lattice in both the iron matrix and steel substrate. In the zones with cracks, pittings and other macrodefects, as well as in the zones with weak adhesion between the coating and substrate, the resistance of induction currents is higher and, hence, the heating temperature is higher too. As a result, the macrodefects in these points are eliminated, the adhesion of coatings strengthens, and the conditions improve for diffusion along the separating boundaries in the composition layer (between the iron matrix and particles of phase II) and between the latter and steel substrate the breakage occurs and new chemical bonding originates. The formation of such chemical bonds as FeB, Fe2B, etc., is possible. In addition to the elements of this system (Fe, B and C), the coatings also contain hydrogen, which accumulated in CEC in the electrodeposition process, and at heating its diffusion occurs with a partial release of H2 into the atmosphere.  The composition Fe -B4C coatings thermally modified, after the electrodeposition can be plated on the surface of the machine parts, which operate under conditions of: 1) high temperatures; 2) lubrication deficit; 3) abrasive wear.