Characterization of Al/B4C–Y2O3 hybrid composites produced by vacuum hot pressing combined with Al2O3–Y2O3 interaction

Abstract

In this study, the Al/B4C/Y2O3 hybrid composites were produced by Al2O3 and Y2O3 interaction via hot pressing. Moreover, the influence of Y2O3 on the properties of Al/B4C 10 wt% was investigated. The hot pressing was performed at 600 °C with pre-oxidized aluminium powder to produce the composites. The microstructure analyses revealed that Al/B4C/Y2O3 hybrid composite production was achieved by Al2O3 and Y2O3 interaction, and the Y4Al2O9 (YAM) phase was obtained in the Al–B4C/Y2O35 % sample. The Y2O3 addition increased the porosity content of the Al/B4C structure. However, wear rate and corrosion resistance of the Al/B4C were enhanced owing to the presence of Y2O3. The wear rate of Al/B4C was reduced from 26.55·10−7 cm3/Nm to 5.68·10−7 cm3/Nm at 15 N test load. The increasing Y2O3 content and the formation of the Y4Al2O9 decreased the corrosion rate of the Al/B4C fom 0.0179 mm/year to 0.0051 mm/year. Also, corrosion damage was shifted from the matrix to the reinforcement zone in Al–B4C/Y2O35 % sample, and the aluminium was protected owing to the presence of Y2O3 and Y4Al2O9.