A3钢在链霉菌和诺卡氏菌共同作用下的腐蚀行为

Corrosion Behavior of Steel A3 under the Combined Effect of Streptomyces and Nocardia sp

采用腐蚀失重法、电化学交流阻抗法(EIS)和表面分析技术研究了A3钢在链霉菌(Stremptomyces)和诺卡氏菌(Nocardia sp)共同作用下的腐蚀行为.结果表明,与单种菌相比,混合菌作用下试样表面的腐蚀倾向增大,阻抗值降低,腐蚀电流密度增加.浸泡21天后,混合菌溶液中A3钢的腐蚀失重速率大于两种微生物单独存在时的腐蚀失重速率之和.扫描电子显微镜(SEM)分析结果表明,混合菌溶液中A3钢表面发生了严重的局部腐蚀,在链霉菌和诺卡氏菌的共同作用下,A3钢的腐蚀程度加剧.

The weight loss method, electrochemical impedance spectroscopy （EIS） and surface analysis methods were employed to investigate the corrosion behavior of steel A3 under the combined effect of Streptomyces and Nocardia sp. Results showed that the combined effect of Streptomyces and Nocardia sp markedly increased the corrosion tendency of steel A3, decreased the impedance value and increased the corrosion current density of the electrode after 21 days of exposure. Corrosion mass loss rate in the mixed colonies solution was more than the sum of the loss rate for each individual microorganism. Scanning electron microscopy （SEM） results indicated that localized corrosion occurred on the steel A3 coupon immersed in the mixed colonies solution. The combined effect of Streptomyces and Nocardia sp aggravated the corrosion of steel A3.