模拟体液中的尿酸对AZ31B镁合金腐蚀行为的影响

Effect of Uric Acid in Simulated Body Fluid on Corrosion Behavior of AZ31B Magnesium Alloy

过去，探讨高尿酸浓度体液中AZ31B锾合金腐蚀状况的研究不多。采用开路电位、交流阻抗谱和失重法等研究了AZ31B镁合金在不同尿酸浓度的模拟体液中的腐蚀行为。结果表明：在模拟体液中尿酸会加快镁合金的腐蚀，但是尿酸加入量与腐蚀速度不是简单的线性关系，尿酸浓度较小时其对腐蚀速率影响较大，当尿酸浓度超过104μmoWL后，镁合金的腐蚀速率不再显著增大；镁合金的失重速率随着浸泡时间的延长而减小，经8～12d的浸泡后，镁合金的腐蚀过程基本达到稳定状态。

The corrosion behavior of AZ31 B magnesium alloy in simulated body fluid containing uric acid was studied with open circuit potential method,electrochemical impedance spectroscopy and weight loss method.Results showed that introducing uric acid in the simulated body fluid accelerated the corrosion process of the Mg alloy,but the dosage of the uric acid was not simply linearly proportional to the corrosion rate of the Mg alloy.Namely,when the concentration of uric acid was relatively low,introducing uric acid had significant effect on the corrosion rate of the Mg alloy in the simulated body fluid.However,when the concentration of uric acid was above 104 μmol/L,the corrosion rate of the Mg steel in the simulated body fluid tended to be stabilized.In general,the mass loss rate of the Mg alloy in the simulated body fluid tended to decline with extending time of immersion,and its corrosion process reached a stable state after 8~12 d of immersion.