EFFECTS OF COAL SLAG CORROSION ON THE MECHANICAL PROPERTIES OF SINTERED alpha-SILICON CARBIDE

摘要

Tubes of sintered SiC were exposed for 500 h in a laboratory furnace to three different coal slags at three temperatures. No corrosive attack or strength reduction was observed after exposure at 1090 deg C. At 1260 deg C the least viscous slag caused formation of corrosion pits and loss of strength. At 1430 deg C formation of iron silicides at the interface between the slag and the base material caused severe loss of strength for slags with the highest and the lowest viscosity, while the specimens exposed to the slag with medium viscosity and medium iron content survived quite well. The results show that mechanical strength can be retained for certain coal slag - temperature combinations.