Plasma treatment of heat-resistant materials

Abstract

Refractory lining of thermal generating units is exposed to chemical, thermal, andmechanical attacks. The degree of fracture of heat-resistant materials depends on the chemicalmedium composition, the process temperature and the material porosity. As is known, a shorttermexposure of the surface to low-temperature plasma (LTP) makes possible to createspecific coatings that can improve the properties of workpieces. The aim of this work is toproduce the protective coating on heat-resistant chamotte products using the LTP technique.Experiments have shown that plasma treatment of chamotte products modifies the surface, anda glass-ceramic coating enriched in mullite is formed providing the improvement of heatresistance. For increasing heat resistance of chamotte refractories, pastes comprising mixturesof Bacor, alumina oxide, and chamot were applied to their surfaces in different ratios. It isproved that the appropriate coating cannot be created if only one of heat-resistant componentsis used. The required coatings that can be used and recommended for practical applications areobtained only with the introduction of powder chamot. The paste composition of 50% chamot,25% Bacor, and 25% alumina oxide exposed to plasma treatment, has demonstrated the mostuniform surface fusion.