The effect of nanometric zirconia particle additives on microstructure and mechanical properties of dense alumina

Abstract

Zirconia additives have favourable influence on mechanical properties of dense alumina polycrystals. It results from the martensitic transformation of tetragonal zirconia particles into monoclinic symmetry at the crack tip propagating through a material. Usually applied zirconia particles were of sub-micrometer or micrometer sizes. In the present work nanometric zirconia particles prepared by hydrothermal crystallization technique were introduced into the alumina matrix. Both, zirconia and alumina powders were homogenized in an aqueous suspension of pH selected on the basis of the zeta (ξ) potential measurements. It was found that this factor influences greatly strength of the resulting powder agglomerates and hence mechanical properties of the sintered material.

Keywords

• Alumina - zirconia
• Ceramic composites