METALLURGICAL PROCESSES OF MELTING AND TRANSFER OF ELECTRODE AND ADDITIVE MATERIALS IN A SLAG BATH IN ELECTROSLAG SOLDERING

Abstract

The article examines the actual problems of the melting process and the transfer of electrode and filler materials during electroslag surfacing. The purpose of the article is to determine the optimal metallurgical processes for obtaining high-quality deposited metal with the necessary indicators of wear resistance. At the beginning of the study, it was established that the rotation of the slag bath up to 150 revolutions per minute does not significantly affect the duration of the stay of the granular additive in the slag, but accelerates the heat exchange processes between the slag and the additive particles, and also increases the relative mass of the slag interacting with the particles. This leads to the intensification of the process of refining the deposited metal. When the rotation frequency of the slag bath is higher than 150 revolutions per minute in crystallizers with a diameter of 100 mm or more, the duration of the particle transfer process increases. Sometimes the granular filler material is not fed to the mirror of the slag bath, but is placed together with the flux on the surface to be welded, or is introduced into the volume of the slag bath, for example, in the form of a tubular electrode filled with an additive. In this case, the particles, having a large specific surface area, melt with much lower heat consumption than is required to melt such a quantity of monolithic metal. It was found that the free transfer of particles in the slag and the subsequent sliding of the particles along the wall of the crystallizer, which can be called two-stage, ensures the complete melting of particles with a large diameter (more than 3 mm) already in the slag layer, without their remelting in a metal bath. It has been proven that when using a liquid additive material, there are no stages of melting, as well as the formation and formation of drops. Not a drop, but a liquid jet of metal interacts with the slag, further interaction occurs at the boundary of the distribution of the metal and slag baths. The main directions of further research into the processes of melting and transfer of electrode and additive materials in the slag bath are determined. Specific tasks for the study of the metallurgical interaction between the floating material and slag are formulated. Further research should be aimed at determining the effectiveness of using electrode and additive materials of different compositions.