Wear Behavior of Nanostructured Al and Al-B4C Nanocomposites Produced by Mechanical Milling and Hot Extrusion

Wear properties of a nanostructured matrix of Al prepared via mechanical milling and hot extrusion were investigated before and after incorporation of B4C nanoparticles. The sample powders were milled for a period of 20 h to produce nanopowders. Mechanical milling was used to prepare nanocomposite samples by addition of 2 and 4 wt% of B4C nanoparticles into the Al matrix. A pin-on-disk setup was used to evaluate the wear properties of the hot extruded samples under dry condition. The results revealed a lower friction coefficient and a lower wear rate for the nanostructured matrix of Al in contrast to a commercial coarse grained Al matrix. The same pattern was also observed in the nanocomposite samples with respect to the base matrix. Hardness values were used to discuss the observed results. Scanning electron microscopy (SEM) was used to analyze the worn surface and wear debris.