抄録
Si3N4-based ceramics such as hot isostatically pressed Si3N4, hot pressed Si3N4, and hot pressed sialons containing 0, 30, 60 and 100% of α phase were corroded by K2SO4 and K2CO3 melts at 1150-1300°C and 925-1150°C, respectively. The surface reaction-controlled shrinking core model adequately described the relationship between the weight loss of the specimen and the time for the corrosion reactions in both K2SO4 and K2CO3 melts. The corrosion rate in K2CO3 melts decreased with increasing the content of Al and Y ions in the specimens. The fracture strength of the specimens corroded by K2SO4 and K2CO3 melts degraded to 2/3-2/5 of the original values before lossing 2% of its weight, and then became almost constant up to 30% of weight loss.
