Study on Tribological Behavior of Surface Micro-arc Oxidation 6061 Aluminum Alloy

Abstract

The surface quality of micro-arc oxidation (MAO) in 6061 aluminum alloy was investigated using a variety of process parameters. The tribological properties of the different MAO surfaces were evaluated using the ‘reciprocating pin-on-disk’ method. Different current densities were selected in order to illustrate the formation mechanism of the MAO layer. Wear test results were used to evaluate the wear resistance ability of the various MAO layers for establishing a wear model. The surface morphology, porosity distribution on cross section, and worn surface of the MAO layers were characterized using a scanning electron microscope (SEM). Different material counterparts and contact conditions were applied to simulate a variety of practical scenarios. The results show that the hardness of the MAO layer formed at the 15 A/dm2condition was the highest among the four kinds of specimens, and the MAO layer formed at the 15 A/dm2 condition had the best wear resistance. This can be attributed to the various size and distribution of the pores and the different ratio of $\alpha$ to $\gamma$ phase in the MAO layers when subjected to different parameters during MAO process.