HUO Xiaodi^1,2, WANG Qing^1*, LIANG Jun², ZHANG Kai^1,2, MU Ming²

(1. School of Science, Lanzhou University of Technology, Lanzhou 730050, China 2. State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of SCEICNES, Lanzhou 730000, China)

Abstract: Plasma electrolytic oxidation (PEO) in Na₂SiO₃-KOH electrolytes with different solid lubricant additives are used to produce solid lubricant-containing PEO coatings on LY12 aluminum alloy. The composition and microstructure of the PEO coating, PTFE-containing PEO coating and graphite/PTFE co-containing PEO coating are analyzed by using fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscope (SEM). The tribological properties of PEO coatings are evaluated on a reciprocating ball-on-disk tribometer. The results show that the solid lubricant additives incorporated successfully into the PEO coatings. PTFE-containing PEO coatings exhibit lower friction coefficient than that of the PEO coatings. The graphite/PTFE-PEO coating has the lowest friction coefficient.

Key words: aluminium alloy; self-lubrication; plasma electrolytic oxidation; polytetra; uoroethylene graphite

E-mail: wangqing@lut.cn

Tribology, Vol. 32, Issue 2, 2012, 133~138