Basalt stone castings with enhanced thermal-shock and acid resistance

Traditional stone castings obtained from petrurgical melts of the basaltic types possess a high chemical resistance in concentrated sulfuric acid and adequate abrasion resistance, but have a relatively low resistance in 20% hydrochloric acid, and a reduced thermal-shock resistance. This is due to the fact that the stone-cast material does not possess a monomineral structure. The low chemical resistance in HC1 and the low thermal shock resistance markedly restrict the application range of stone cast articles. A study was made about the possibility of using Berestovets basalt to obtain stone castings possessing enhanced shock and acid resistance (20% HC1). The usual additives for the basalt, increasing the crystallization stability of the melt, i.e., dolomite, magnesite and horneblend, were replaced by talc slate - a waste product from the mining benefication complex Ingulets GOK. The above additives contain a significant amount of magnesia which improves the crystallization capacity of the melt, reduces the crystallization temperature of the cast material, and contributes to the formation of the microcrystalline, dense structure of the casting.