INCREASING OF GLOW DISCHARGE STABILITY IN WELDING BY MEANS OF MULTISECTIONAL ELECTRODE SYSTEMS

Abstract

Background. The glow discharge has been widespread as a source of surface heating for diffusion welding and soldering thanks to the possibility of regulation within a wide range of energy excursions in a heating spot. At the same time, due to the pressures inherent in these processes, certain violations have been identified, mainly due to the partial or complete loss of its stability and, as a result, its transition to a more stable form of gas discharge – an electric arc.Objective. The purpose of the paper is to provide stabilization of the burning process of a high-current glow discharge in regimes that are used in precision welding processes at discharge currents of 10 A, and gas pressures of 1.33–13.3 kPa.Methods. Using the methods of the theory of gas discharge physics, electrodynamics and electromagnetism, the main causes of the appearance of external perturbations and instabilities that lead to the emergence of a stable arc discharge on the local sections of the surfaces of the welded parts were determined.Results. It is established that at a constant current of discharge the application of a 5-section anode unit with a traveling electric field increases the region of stable existence of a glow discharge by 1.5–1.7 times in comparison with a similar electrode system with a stationary electric field. The application of this system, when heated by glow discharge, can also increase the energy density in the heating spot by a stable glow discharge by 2.6 to 2.9 times compared with the use of the anode of a continuous section.Conclusions. The stabilization of the power current flare discharge in the conditions of welding heat can be achieved by applying multisection electrode systems, namely by replacing the solid (contour) anode with a sectional one. However, such a system does not exclude the possibility of melting of parts due to the stabilization of the arc discharge on a separate anode section (and the corresponding section of the cathode).