Wear and corrosion resistance of Al ion implanted AZ31 magnesium alloy

• Published in: Surface & coatings technology 2007-02, Vol.201 (9), p.5182-5185
• Main Authors: Lei, M.K., Li, P., Yang, H.G., Zhu, X.M.
• Format: Article
• Language: English
• Subjects: Applied sciences; AZ31 magnesium alloy; Contact of materials. Friction. Wear; Corrosion; Corrosion environments; Exact sciences and technology; Ion implantation; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Metals. Metallurgy; Wear
• ISSN: 0257-8972; 1879-3347
• DOI: 10.1016/j.surfcoat.2006.07.091

The Al ion implantation into AZ31 magnesium alloy is carried out in a MEVVA 80-10 ion implantation system with an ion implantation dose ranging from 2 × 10 16 ions/cm 2 to 1 × 10 17 ions/cm 2 at an ion energy of 40–50 keV. The concentration–depth profile of implanted Al in AZ31 magnesium alloy was a Gaussian-type distribution in the depth up to about 840 nm with the maximum Al concentration up to about 10 at.% measured by using Rutherford backscattering spectrometry (RBS). The microstructure, which is composed of α-Mg phase, intermetallic β-Mg 17Al 12 and MgO phases is observed on the ion implanted samples by X-ray diffraction (XRD). Potentiodynamic anodic polarization curves in 0.01 M NaCl solution with pH = 12 showed that the increase of corrosion potential and pitting breakdown potential and the decrease of the passive current density are obtained for the Al ion implanted samples. The Al ion implanted AZ31 magnesium alloy with the ion implantation dose of 2 × 10 16 ions/cm 2 achieved the high pitting breakdown potential to about − 1000 mV(SCE). The wear rate of the Al ion implanted AZ31 magnesium alloy is approximately reduced by 30–40%, compared with that of the unimplanted sample.