Effect of Cobalt Oxide Addition on Alumina Sintering

Abstract

The present work describes the effect of cobalt oxide addition on alumina sintering. Here cobalt oxide is added as a do pant to enhance densification of alumina. In this project the do pant cobalt oxide is added by two ways firstly by direct addition of cobalt oxide to alumina by wet mixing and secondly by infiltration of cobalt nitrate solution into precalcined alumina pellets. In direct mixing process 1 and 2 mol% of cobalt oxide is added to alumina and in infiltration process infiltration is carried out for different time period such as 10, 20 ,30 and 40 minutes. Then the prepared pellets are dried and sintered at 1550oC and 1600oC with a soaking time for 3hrs. The pellets are then characterized for densification study, phase analysis and micro structural analysis. Final results reveal that the doped samples acquire a better density (~92% of theoretical density) than undoped samples (~ 86% of theoretical density) when sintered at 16000C.