| Summary: | Alumina-silicon carbide (Al<sub>2</sub>O<sub>3</sub>–SiC) composites of varying compositions (15, 20, 25 and 30 vol.%)–SiC were produced by the ball milling of Al<sub>2</sub>O<sub>3</sub> and SiC powders, followed by spark plasma sintering. The samples were sintered at a temperature and pressure of 1600 °C and 50 MPa, respectively, thermally etched at 1400 °C and mechanically fractured by hammer impact. The effect of SiC additions to monolithic Al<sub>2</sub>O<sub>3</sub> on the densification response, microstructural and phase evolutions, and fracture morphologies were evaluated. The wear performance of the composites using a ball-on-sample configuration was evaluated and compared to that of monolithic Al<sub>2</sub>O<sub>3</sub>. In addition, the corrosion performance of the composites in a 3.5% NaCl solution was examined using open circuit potential and potentiodynamic polarization assessments. SiC additions to monolithic Al<sub>2</sub>O<sub>3</sub> delayed densification due to the powder agglomeration resulting from the powder processing. SiC particles were observed to be located inside Al<sub>2</sub>O<sub>3</sub> grains and some at grain boundaries. Intergranular and transgranular fracture modes were observed on the fractured composite surfaces. The study has shown that the Al<sub>2</sub>O<sub>3</sub>–SiC composite is a promising material for improved wear resistance with SiC content increments higher than 15 vol.%. Moreover, the increase in SiC content displayed no improvement in corrosion performance.
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