Investigation of alkali resistance of fireclay castable with silica sand additive

Abstract

In this paper, the properties and the alkali resistance of MСC type refractory castable with fireclay fillers of different grades (BOS125, BOS135, BOS145), were studied. To improve the alkali resistance of the investigated castables, ground quartz sand additive was used. The investigations (crucible test with potassium carbonate salt) show that a thin protective glassy layer (about 700 μm deep in castable with BOS145) is formed on the surface of castable specimen and the specimens withstand more than 20 cycles at temperature 1100oC and more than 5 cycles at temperature 1200oC regardless of fireclay grade and type of castable.