Binding property of ρ-alumina for α-alumina slurry - effect of specific surface area of α-alumina on hardening of slurry-

摘要

The effect of the specific surface area of addedρ-alumina on hardening ofα-alumina slurry was investigated by the measurement of the penetration resistance of u-alumina slurry. p-alumina was made by the heating of Al(OH) {sub}3from 200 to 700°Cin vacuum. The penetration resistance increased with increasing holding time. The holding time required to reach the same penetration resistance decreased with increasing specific surface area ofρ-alumina, when it contained neither Al(OH) {sub}3norη-alumina. In the case where Al(OH) {sub}3 remained inρ-alumina (heat treated below 300°C), the hardening of the slurry proceeded more rapidly than that of the slurry without Al(OH) {sub}3, exhibiting about the same specific surface area.Whenη-alumina was formed (heat treated above 600°C),then the hardening of the slurry proceeded more slowly than that of the slurry withoutη-alumina.