Friction and wear properties of aluminum-particulate graphite composites

Abstract

Aluminum alloy matrix composites containing 3, 6 and 9 wt.% particulate graphite were produced and their friction, wear, and tensile properties were determined. The composite fabrication process consisted of adding nickel-coated graphite particles into a partially solidified and vigorously agitated Al-7%Si-1%Mg alloy, followed by remelting and casting into ingots. The coefficients of friction and wear of the as-cast and liquid-forged composites were determined by a Falex lubricant test machine. It was found that the friction and wear properties of both as-cast and liquid-forged alloys considerably improved with addition of graphite. While the tensile strength and ductility of composites containing 3% graphite were comparable with those of the matrix, increasing graphite content reduced these properties.