Optimization of corrosion resistance and mechanical properties of Al2O3‐Cr2O3 refractories for waste incinerator

Abstract

AbstractThe corrosion resistance and mechanical properties directly affects the operation and service life of Al2O3‐Cr2O3 refractories used in waste incinerators. In this study, ZrO2 particles were introduced via vacuum impregnation to adjust microstructure and properties of Al2O3‐Cr2O3 refractories. The results showed that the impregnated ZrO2 particles and increasing impregnation times resulted in the decreased median pore size and increased compactness, and mechanical strengths of refractories were elevated from the inhibited cracks propagation by ZrO2 particles. The decreased amounts of large pores and increased amounts of small pores from the filled ZrO2 particles inhibited penetration of low melting point phases, and the formed CaZrO3 phase from the reactions between corrosion reagent and ZrO2 particles increased the viscosity of penetrated corrosion reagent, resulting in the decreased penetration index from 8.57% to 2.58%. Meanwhile, the filled ZrO2 particles around alumina particles prevented reactions between molten corrosion reagent and alumina, leading to the decreased corrosion index from 3.78% to .74%. The decreased pore size and formation of CaZrO3 phase were primary factors that enhanced the penetration resistance. And formation of wrapped layers from ZrO2 particles around alumina particles presented prominent effects on the strengthened corrosion resistance of Al2O3‐Cr2O3 refractories.