Influence of Strontium Oxide on Mechanical Response of Zirconia Toughened Alumina

Abstract

Zirconia toughened alumina (ZTA) is widely used in total hip arthroplastices. ZTA components are comprised of an alumina-rich composition where zirconia is evenly dispersed in the alumina matrix. Incorporation of strontia (SrO) in ZTA matrix is subject to enhance the fracture toughness and strength through development of elongated grains and cell proliferation in vivo also. In this perspective, the aim of this investigation was to study the effect of SrO on the physical and mechanical properties of ZTA. ZTA pellets were prepared with varying weight percentage of strontia as dopant. The pellets were uniaxially pressed at 5 ton force and then sintered at 1600oC for 3 hours. The effects of SrO addition on properties such as density, microstructure, Vickers hardness, fracture toughness, compressive strength and tribology are studied. The SrO profoundly reacts with alumina and forms strontium aluminates at an optimum processing conditions. These strontium aluminates have elongated structure, which reduces the resultant grain size of matrix and enhancement of sintered density. This developed microstructure assists to improve the mechanical and tribological response of strontia doped ZTA composites.