Tribological properties of powder solidification extruded Al-based composites

Abstract

The effect of fabrication methods on tribological properties, such as friction coefficient and specific wear rate, was investigated using several Al, its alloys and Al-based composites. Tribological properties of these materials were evaluated under dry conditions at room temperature using a ball-on-disk wear tester. The friction coefficient in the casting process decreased gradually, while the friction coefficient in the powder solidification extrusion decreased suddenly. This is due to that the reinforcing particles in the powder solidification extrusion are deposited on the sliding traces and the base metal portion is ejected to the edge. The presence of deposited reinforcing material is also assumed to suppress of specific wear rate. The wettability of pure Al and the reinforced material showed that samples with a large surface free energy difference showed a sudden decrease in the friction coefficient due to early delamination of the reinforced materials. It is concluded that (1) the preparation of samples by powder solidification extrusion and (2) the wettability of the material is effective in improving tribological properties.