Directly-Bonded Periclase-Chromite Refractory Corrosion Mechanism in an RH-Degasser Suction Pipe

Abstract

Results are provided for a study of refractory objects based on fuzed periclase after service in the suction pipe of an RH-degasser in two metallurgical enterprises. In one enterprise the pipe operates in contact with slag, containing fluorspar with an alumina slag-forming component as a homogenizing addition, and in the second with slag for whose homogenization only fluorspar is used. In both cases, but in different pipe service conditions, there are 100 melts, and the operating duration is 1550 – 1800 min. It is established that the depth of molten slag component filtration into refractory depends on the form slag homogenizing additive in the steel-pouring ladle. Slag containing a combination of feldspar with alumina slag-forming additive penetrates into the refractory microstructure to a greater depth, which leads to a change in the initial phase composition of an object with formation of a considerable amount of secondary phases.