经硅等离子体注入的纯镁电化学腐蚀性能的研究

Effects of Silicon Plasma Immersion Ion Implantation on Electrochemical Corrosion Properties of Pure Magnesium in Simulated Body Fluid

优越的力学性能,理想的生物相容性和独特的降解特性使镁及其合金成为革命性的金属生物材料,但耐蚀性差限制了其应用潜力的发挥,为此提高其耐腐蚀性成为重要的研究课题.等离子体注入是既有效又方便的表面改性技术.本文对纯镁进行硅等离子体注入表面改性,通过光电子能谱检测硅元素注入深度和化合价态,并使用动电位极化测试和交流阻抗谱评价处理前后样品在模拟体液中的腐蚀行为.实验结果表明,经硅等离子体注入的纯镁表面形成一层由二氧化硅和氧化镁组成的复合氧化膜.在电化学测试中,处理后的样品呈现较高的腐蚀电位和较低的腐蚀电流,容抗环明显增大.这些结论均表明硅注入后在纯镁表面形成的复合氧化膜减缓了腐蚀速率,提高了耐腐蚀性能.

Magnesium（Mg）and its alloys are revolutionary metallic biomaterials due to their excellent mechanical characteristics,desirable biocompatibility,and unique biodegradable property.Unfortunately,the inherent poor corrosion resistance restricts the potential application.In this respect,many attempts have been made to improve the corrosion resistance.Plasma immersion ion implantation is an effective and efficient three-dimensional surface modification technique.In this work,silicon is implanted into the pure magnesium,and X-ray photoelectron spectroscopy is used to characterize the materials.The corrosion properties are systematically studied by potentiodynamic polarization tests in simulated body fluids.The process improves the corrosion resistance as inferred from the higher Ecorr and lower Icorr compared to the untreated samples,and the EIS curves further confirm the better electrochemical stability of the silicon implanted Mg samples.