The influence of Y3+ and Mg2+ dopants on the transparency behavior of alumina ceramics

Abstract

The effect of salt solution of magnesium and yttrium addition on the transparent alumina polycrystalline was investigated in the present study. This solution is ionized in the slurry. The ions were adsorbed onto the charged alumina surface by the electrostatic mechanism. Due to the addition of salts solution at the casting stage, the distribution of dopant was uniform. Therefore no secondary phase has been formed in the sample after sintering. The added salts eliminated the intragranular porosity and prevented the growth of the grains. After optimizing the amount of the dispersant (1.3 wt%) and preparing the slurry by using a 3D-mixer, the samples were sintered at a temperature of 1250 °C and at the rate of 20 °C/min by the SPS method, the transparency was increased from 18 to 33% by adding salt solution of the Mg2+ and Y3+ as dopant. Also, the grain size was decreased from 27.37 to 4.29 μm in the sample with dopant, therefore the hardness was increased from 1814 to 2279 HV10.