The Specific Features of Manufacturing Corrosion-Resistant Fluorophlogopite Products by Electric Arc Melting with the Use of Carbide Powder Modifiers in Conditions of SmallScale Production

Abstract

Introduction. The reliability and efficiency of industrial metallurgical units such as chlorinators, electrolyzers, and others operating in aggressive acid and alkaline environments at high temperature are primarily determined by their service life.
Problem Statement. The corrosion-resistant protective layer of the inner surfaces of metallurgical units composed of relatively small individual protective elements has a drawback, namely, a joint made of mounting compounds that have a much lower resistance.
Purpose. The purpose is to create technologies for small-batch and periodic production of dense cast heat- and corrosion-resistant products in the form of massive shaped castings from fluorosilicate melt. 

Material and Methods. Fluorine- and potassium-containing mineral compounds have been used as charge materials due to their availability and manufacturability. The melting and casting conditions have been evaluated based on the current-voltage characteristics of the power source of the electric arc furnace. The mineral composition and microstructure of the cast material have been studied by the crystal optical method in transparent sections and uncut sections.
Results. Optimization of the batch composition and melting conditionsallows reducing the melting time of fluorophlogopite melt 2.3 times and the total energy consumption of melting by 38%. The use of carbide modifiers ensures a homogeneous structure in the outer skin and the main part of the casting, with the size of fluorophlogopite crystals ranging from 0.10 to 0.15 mm.
Conclusions. The choice of raw materials for fluorophlogopite casting significantly affects the conditions of melt formation and the structure of the cast material. To achieve the purpose of the research, the authors have proposed a technology for the manufacture of cast fluorophlogopite products, which combines the selection of charge mineral materials, the optimization of the electric arc melting conditions for obtaining fluorosilicate melt, and the castings structure control by means of modification with silicon and boron carbide powders.