Castings from corundum-baddeleyite ceramics, their properties and using for wear resistant materials, pipings etc.

摘要

The castings from corundum-baddeleyite ceramics are used as a refractory and wear resistant material and their chemical composition consists from 13-17 wt. percent SiO_2, 49-52 wt. percent Al_2O_3, 30-33 wt. percent ZrO_2 and rest oxides of Ti, Fe, Na, K, Ca. In this paper the research of technological and foundry parameters and chemical macroheterogeneity of castings from corundum-baddeleyite ceramics are described. The main results are as follows: The ceramics was melted in the electric arc furnace and the liquid melt temperature in the electric arc furnace and in the castings was measured by means of special thermocouples. The solidification constants K (after Chvorinov) in (cm.min.~(1/2)) of two kinds of foundry moulds were measured. The macroheterogeneity of Na_2O, Al_2O_3, SiO_2, ZrO_2, K_2O, CaO, TiO_2, Fe_2O_3 and HfO_2 oxides phase constitution of this ceramics were established. Th influence of the filtration of liquid carbon steel by means of the corundum-baddeleyite filter on chemical micropurity of this steel has been described.