(1. 中南大學(xué) 粉末冶金國家重點實驗室，長沙 410083；2. 中南大學(xué) 湘雅醫(yī)院，長沙 410008)
摘 要: 采用粉末冶金和熱壓燒結(jié)的方法制備以MgO陶瓷粉末(質(zhì)量分數(shù)分別為5%、10%和20%)為增強相的MgO/Mg鎂基生物復(fù)合材料, 并用XRD和SEM表征其顯微組織結(jié)構(gòu)。以純鎂金屬作為對照樣，分別采用失重腐蝕、動電位極化掃描和電化學(xué)阻抗譜研究不同MgO含量的鎂基復(fù)合材料在模擬體液(簡稱SBF)中的腐蝕降解速率和腐蝕行為。結(jié)果表明：MgO/Mg鎂基復(fù)合材料與純鎂金屬具有相同的腐蝕機制，MgO在鎂基體中的均勻、連續(xù)分布，可以提高鎂基復(fù)合材料整體的耐腐蝕性能，其耐蝕性隨著MgO含量的增加而改善，20%MgO/Mg復(fù)合材料表現(xiàn)出最好的耐腐蝕性能。
關(guān)鍵字: 鎂基金屬復(fù)合材料；粉末冶金；耐蝕性；極化曲線；電化學(xué)阻抗譜
MgO/Mg biocomposite materials
（1. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
2. Xiangya Hospital, Central South University, Changsha 410008, China）
Abstract:The MgO/Mg biocomposite materials containing 5%, 10% and 20% (mass fraction) MgO as reinforcement phase were fabricated by powder metallurgy and hot press sintering process. Pure Mg specimen was made following the same procedure and used as control experiment. Their microstructures were characterized by XRD and SEM. The corrosion biodegradable properties of MgO/Mg biocomposite materials with different MgO contents were studied in the simulated body fluid (SBF) by weight loss test and electrochemical measurements including potentiodynamic polarization and electrochemical impedance spectra (EIS). The results show that the MgO/Mg composite materials share the same corrosion mechanism with pure Mg metal. The uniform and consecutive dispersion of MgO in Mg matrix plays an important role in the improvement of corrosion resistance of composite materials. The corrosion resistance increases with the increase of MgO addition. The MgO/Mg composite material with 20% MgO exhibits the best enhanced corrosion resistance.
Key words: Mg-based metal matrix composites; powder metallurgy; corrosion resistance; polarization curve; electrochemical impedance spectra
