Quantitative Evaluation of the Interaction Between Wear and Corrosion on Mg-3Gd-1Zn Alloy in Simulated Body Fluid

摘要

As potential temporary implants, biodegradable magnesium (Mg) alloys will undergo fretting friction and corrosion simultaneously in human body. Aiming at illustrating the interaction between wear and corrosion of Mg alloys, wear and corrosion rates in simulated body fluid (SBF) were quantitatively evaluated on Mg-3Gd-1Zn (wt.%, GZ31) alloy. Wear behaviors of the alloy in SBF were compared with those under dry sliding condition, and corrosion rates of the alloy accompanied with wear were also compared with those without wear in SBF. The characteristic parameters of wear tracks were collected by 3D surface profile. The results indicated that the friction coefficient in SBF was much lower as compared to that under dry sliding condition. Owing to the protection of Mg(OH)(2) and lubrication of SBF, wear was significantly restricted, but due to the galvanic corrosion between matrix and wear debris, corrosion was seriously aggravated. Most of the mass loss was attributed to corrosion rather than wear for the wear test in SBF.