Abstract
The present work was done to determine whether the preferred orientation in hot-pressed alumina was actually rearranged by high temperature creep with a direction parallel or perpendicular to hotpressing direction and also the creep rate was dominated by a creep direction concerned with the preferred orientation.
After crept, it was found that c-axes of alumina crystals which are observed to be parallel to hot-pressing direction in sintering are changed to be parallel to creep direction when the direction is set to be perpendicular to the pressing direction, although the preferred orientation is not changed by creep and tended to be strong itself in creep with the direction parallel to hot-pressing. These behavior of preferred orientation by creep may be mainly associated with grain rotations caused by grain-boundary sliding.
From a relationship between compressive stress and creep rate as a function of creep direction, it is evident that the creep deformation is accelerated in the case of creep with a direction perpendicular to hot-pressing direction because of grain rotations.
