Influence of impurities in Al2O3 ceramics on hot corrosion resistance against molten salt

Abstract This report describes an investigation of the influence of impurities of Al 2 O 3 on the hot corrosion resistance against V 2 O 5 –Na 2 SO 4 molten salt. Thickness of damage zone in Al 2 O 3 ceramics whose purity is high depends on the holding time linearly. On the other hand, thickness of damage zone in Al 2 O 3 whose purity is relative low depends on square root of holding time. In the impurities, SiO 2 affected the corrosion rate of Al 2 O 3 especially. Grain boundaries are suffered from hot corrosion. SiO 2 would influence the diffusion rate of corrosive elements through grain boundaries and the corrosion rate.