Quantitative description of the spinel phase (NiAl2O4) located into Al2O3 matrix

Abstract

The presented work focuses on the quantitative description of the spinel phase (NiAl2O4) located into Al2O3 matrix. Three series of samples were prepared. Series I, II and III containing following amount of nickel powder: 0.21% vol, 0.43% vol and 1.3% vol respectively. In order to obtain nickel aluminate spinel sintering was carried out in an oxidizing atmosphere (air). Based on the SEM observation and XRD analysis the presence of spinel phase was confirmed in all samples. Difference in volume fraction of the Ni in the compacts before sintering, resulted in the different content of the spinel phase in the final material. All tested composites were characterized by homogeneous distribution of NiAl2O4 in the whole volume of the material. The purpose of the study was also the use the stereological analysis to determine the shape parameters of new phase.