Study of Mechanical Properties of Magnesium Oxide Doped Alumina (Al_2O_3) and Yttria Stabilized Zirconia (YSZ) Composite for Medical Applications

摘要

The aim of this research is to study the mechanical properties such as hardness, wear resistance etc, of the magnesium oxide (MgO) doped alumina (Al_2O_3) and yttria stabilized zirconia (YSZ) composite, We first prepared MgO-doped Al_2O_3 (denoted as Al_4) by mixing Al_2O_3 powder and 0.4 wt% of MgO powder. After that Al_4 powder was mixed YSZ powder, with the formula [(x)Al_4 - (100-x)YSZ] when x was varied from 0 - 100 by wt%. The samples were sintered at 1450, 1500, 1550, 1600 and 1650°C. In addition, microstructure of the surface was studied employing both optical and scanning electron microscopes. The hardness of the surface was investigated by Vickers indentation technique and pin on disk apparatus was employed for wear rate measurement. The results showed that the density and volume shrinkage decreased with the increase of Al_4 content. The grain size and porosity of the specimens tend to decrease when the sintering temperature increases. The hardness and wear resistance of the samples increased with the increase of Al_4 up to 90%. It was also found that the material is not toxic to the body.