石墨烯对AZ31镁合金在模拟体液中腐蚀性能的影响

镁合金具有良好的生物相容性和降解性能,在生物医疗领域具有广泛的应用前景,但镁合金耐蚀性较差成为制约其推广应用的瓶颈。本文针对石墨烯纳米片(GNPs)增强镁合金AZ31+xGNPs(x=0.0%、0.1%、0.3%、0.6%),开展金相显微镜(OM)、X射线衍射(XRD)、扫描电子显微镜(SEM)与能谱(EDS)、失重实验和电化学测试等试验,以探索石墨烯对镁合金AZ31在模拟体液(SBF)中腐蚀性能的影响。试验结果表明,石墨烯(GNPs)的添加并未改变原有镁合金的物相,且细化AZ31镁合金晶粒,改善晶粒大小分布的不均匀性。随石墨烯含量的增加,AZ31镁合金在SBF模拟体液中的流失重量越少,AZ31镁合金的腐蚀速率,腐蚀电位与腐蚀电流密度也越低。分析表明,石墨烯增强镁合金AZ31在SBF模拟体液中的耐腐蚀性能得到增强,且随着石墨烯(GNPs)含量的增加而得到增加。本文的研究可为制备耐腐蚀镁合金及控制其腐蚀速率提供具有实际意义的试验数据。

Effect of graphene on the corrosion performance of AZ31 magnesium alloy in simulated body fluids

Magnesium alloys have good biocompatibility and degradation properties and have a wide application prospect in the biomedical field, but the poor corrosion resistance of magnesium alloys has become a bottleneck limiting their popularization and application. In this paper, for graphene nanosheets (GNPs) reinforced magnesium alloy AZ31+xGNPs (x=0.0%, 0.1%, 0.3%, 0.6%), metallographic microscopy (OM), X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy spectroscopy (EDS), weight loss experiments and electrochemical tests were conducted to explore the effect of graphene on the corrosion performance of magnesium alloy AZ31 in simulated body fluid (SBF). The experimental results showed that the addition of graphene (GNPs) did not change the physical phase of the original magnesium alloy, and refined the AZ31 magnesium alloy grains and improved the inhomogeneity of grain size distribution. With the increase of graphene content, the less weight loss of AZ31 magnesium alloy in SBF simulated body fluid, the lower corrosion rate, corrosion potential and corrosion current density of AZ31 magnesium alloy.The analysis showed that the corrosion resistance of the graphene-reinforced magnesium alloy AZ31 was enhanced in the SBF simulated body fluid and increased with the content of graphene (GNPs). The study in this paper can provide practical experimental data for the preparation of corrosion-resistant magnesium alloys and the control of their corrosion rates.