The structural ceramic materials are important because they are usually lightweight, harder than metals, resistant at higher temperatures and also present an impressive series of mechanical properties, including good mechanical strength in extreme conditions. The alumina based materials and composites are of great importance for ballistic protection. The aim of the present paper is focused on behavior of various alumina types after being sintered in different conditions . The materials used in present study are α-Al2O3 powder (from 3 different sources) and additions of different rare-earth oxides (La2O3, Y2O3, Nd2O3) [1] in two proportions: 500 ppm and respectively 1000 ppm.
The Al2O3 dense ceramics were obtained by various sintering environments, using both traditional sintering ways at temperatures of 1500 ° C (electric furnace) and 1815° C (gas furnace) and a non-conventional technique (cold plasma sintering).
After sintering the samples were analyzed by X-Ray diffraction and scanning electron microscopy (SEM). Ceramic properties like contraction, absorption, porosity, and relative density were also determined.
The final conclusions highlight o series of interpretations and correlations of the sintering parameters with the properties of the sintered materials.