NANOMECHANICAL AND CORROSION PROPERTIES OF ZK60 MAGNESIUM ALLOY IMPROVED BY GD ION IMPLANTATION

摘要

Gadolinium (Gd) ion implantation with doses from 2.5 x 10(16) to 1 x 10(17) ions/cm(2) into ZK60 magnesium alloy was carried out to improve its surface properties. X-ray photoelectron spectroscopy (XPS), nanoindenter, electrochemical workstation and scanning electron microscope (SEM) were applied to analyze the chemical composition, nanomechanical properties and corrosion characteristics of the implanted layer. The results indicate that Gd ion implantation produces a hybrid-structure protective layer composed of MgO, Gd2O3 and metallic Gd in ZK60 magnesium alloy. The surface hardness and modulus of the Gd implanted magnesium alloy are improved by about 300% and 100%, respectively with the dose of 1 x 10(17) ions/cm(2), while the slowest corrosion rate of the magnesium alloy in 3.5 wt.% NaCl solution is obtained with the dose of 5 x 10(16) ions/cm(2).