Anti-Wear Property of Aluminum⁻Silicon Alloy Treated by Chemical Etching, Mechanical Honing and Laser Finishing.

Abstract

To enhance the anti-wear property of aluminum–silicon (Al–Si) alloy, three processing technologies—chemical etching, mechanical honing and laser finishing—were compared in terms of their effects on anti-wear performance. The treated Al–Si alloy cylinder liner samples were worn against a piston ring by a reciprocating sliding tribotester; the anti-wear performance was represented by the friction coefficient and wear loss; and the wear mechanism was determined by establishing stress contact models. The results showed that the best time for both the chemical etching and mechanical honing treatments was 2 min, and the optimal laser power was 1000 W for the laser finishing treatment. The three processing technologies could all remove the aluminum layer and make the silicon protrude on the surface to avoid the plastic flow of aluminum during the friction process. The laser finishing could not only protrude the silicon particle but also make its edge rounded and smooth, which decreased the stress concentration. Therefore, the Al–Si alloy cylinder liner treated with laser finishing had the best anti-wear performance.