Study of the corrosion resistance on nano-ZrO2 doped MgO ceramic composites by copper slag.

Abstract

This study investigated the corrosion mechanism on 100 wt. % MgO and 95 wt. % MgO with 5 wt. % nano-ZrO2 ceramic composites. First, MgO powder and powder mixtures (MgO + nano ZrO2) were uniaxially and isostatically pressed and, then, they were sintered at 1650 °C. Corrosion by copper slag was studied with sintered samples. Physical properties, microstructure and penetration of the slag in the refractory were studied. Results reveal that ZrO2 nanoparticles enhanced the densification of the samples, promoting grain growth due to diffusion of vacancies during sintering process. Additionally, magnesia bricks were severely corroded, if compared with those doped with nano-ZrO2, due to the dissolution of MgO grains during the chemical attack by copper slag.