Investigation of abrasion in Al–MgO metal matrix composites

In this study, the effects of reinforcement volume fractions on abrasive wear behavior were examined in Al–MgO reinforced metal matrix composites of 5%, 10% and 15% reinforcement – volume ratios produced by melt-stirring. Abrasive wear tests were carried out by 60, 80 and 100 mesh sized Al2O3 abrasive papers and pin-on-disc wear test apparatus under 10, 20 and 30 N loads at 0.2 m/s sliding speed. The mechanical properties such as hardness and fracture strength were determined. Subsequent to the wear tests, the microstructures of worn surfaces were examined by scanning electron microscope analyses. While increased MgO reinforcement volume fraction in the composite resulted increased hardness, fracture strength was determined to decrease. Additionally, it was found that increased MgO reinforcement volume fraction in the composite was accompanied with increased wear loss and porosity as well as reinforcement – volume ratio was identified to be significant determinants of abrasive wear behavior.