Properties of Alumina Powder Prepared by Precipitation Method (III) : Sintering Behavior

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J. Korean Ceram. Soc. > Volume 25(5); 1988 > Article

Journal of the Korean Ceramic Society 1988;25(5): 465.

침전법으로 제조한 Alumina 분말의 특성(III) : 소결거동

홍기곤, 이홍림

연세대학교 공과대학 요업공학과

Properties of Alumina Powder Prepared by Precipitation Method (III) : Sintering Behavior

ABSTRACT

Alpha alumina powder with fine particle size and narrow particle size distribution was prepared by precipitation method using Al2(SO4)3.18H2O as a starting material. The alpha alumina powder was prepared by calcining aluminum hydroxide which was formed under various pH values. The sinterabilityof alpha alumina powder and the effect of MgO on the sinterability of alpha alumina powder were investigated. The sinterability of alpha alumina powder was the order of pH=10≒pH11>pH=7≒pH9, and alpha alumina obtained from boehmite which was prepared by precipitation method reached to 97.5% of theoretcal density by the pressureless sintering. The effect of MgO on volume shrinkage of alumina was very slight in the initial sintering stage but remarkable in the final sintering stage. It was also found that MgO controlled effectively the grain growth of alumina.