Dry sliding wear of an Al2O3 continuous fibre reinforced Al-Cu alloy against steel counterface

The tribological properties of Al2O3 continuous fibre reinforced Al-4.43 wt %Cu alloy composites with a fibres' volume fraction of about 0.55 were measured for five types of fibre orientations under a dry sliding contact with a bearing steel. Fibres were in a plain perpendicular to wear surface and parallel to sliding direction, and had the angles 0°, 45°, 90°, or 135° with respect to the direction of motion of the counterface; or were anti-parallel the sliding direction. The results show obvious dependence of wear characteristics on fibres orientation: for the 45°, 90°, and 135° orientations, the larger the fibres' angle, the lower the volume loss; while the 0° orientation resulted in a higher steady-state wear rate than those of the 45°, 90°, and 135°, orientations, except that the anti-parallel orientation caused the highest volume loss at all sliding distances. The wear mechanism was inferred as a oxidation-microgrooving process through the analyses of worn surface and subsurface with the aid of optical microscope and scanning electron microscope. Also it was found that the fibres' broken and subsurface deformation had played an important role in causing wear anisotropy.