Investigation of the tribological behavior of an aluminum alloy with embedded materials

Aluminum alloy-based (LY-12) composites were made by embedding pins of bear ing steel, plain carbon steel, brass, copper, graphite, and polytetra-fluor oethylene (PTFE). The surface area ratio of the embedded phase was 39.1%. T he tribological behavior of the embedded composites was evaluated under dry friction and lubricated with a bonded solid lubricating film outer-layer o n a reciprocating friction and wear tester at ambient conditions. The morph ologies of the worn surfaces and of the transfer films on the counterpart s urfaces were observed with a scanning electron microscope. The tribological behavior of the embedded composites was highly dependent on the hardness o f the embedding materials. Friction and wear of Al alloy can be drastically reduced by proper embedding, but embedding with solid lubricants such as g raphite and PTFE does not help. Friction and wear behaviors were different in sliding against Al and plain carbon steel. The observation of the worn c omposite surfaces by SEM indicates that wear of Al-based composite blocks i s characterized by plowing, severe adhesion, and plastic deformation. (C) 2 001 Elsevier Science B.V. All rights reserved.