Technological Processes of the Electrocontact Welding of Functional Coatings: Part 2

Abstract—Electrocontact welding (ECW) is a promising resource-saving technology for producing functional coatings from waste materials in tool and machine-building production. A clear technique is necessary for choosing materials, equipment, and tools, the sequence and description of operations, and technological parameters (modes) that influence the properties and quality of the coatings produced by this method. To develop a technique for producing, strengthening, and restoring machine parts, functional ECW coatings are studied using a 011-1-10 Remdetal setup. The welding pulse and pause durations are set using an RVI-501 controller. The welding current is calibrated using a 5-mm-thick MM copper strip and an IST-02 welding current meter. An analysis of the electrical resistance of the ECW joint zone shows that the optimum compression force of welding electrodes on a 65G steel plowshare is 1.7 kN for a U12 steel tape. To ensure the maximum process efficiency and complete overlap of weld spots (accounting for the relative movement of electrodes and the part), dependences are derived to determine the following main ECW parameters for all schemes and equipment options: welding current, pulse duration and pause time, electrode compression force, welding speed, weld spot overlap coefficients, and cooling fluid flow rate. Their influence on the process and the coating quality is discussed. The proposed algorithm for calculating and setting welding parameters simplifies the application of the technology and improves the coating quality by minimizing defects caused by parameter errors. The algorithm can be used in machine-building and repair production for designing processes to produce functional coatings for hardening and restoring machine parts.