采用失重法、表面分析技术和电化学测试技术研究了45钢在硫杆菌和假单胞菌协同作用下的腐蚀行为。结果表明,与单种菌相比,腐蚀初期两种菌混合作用下45钢平均腐蚀速率受到明显抑制。随浸泡时间延长,30 d时混菌体系中电极电化学阻抗值较单菌体系减小,腐蚀电位降低,腐蚀电流密度增大,混菌逐渐加速了金属腐蚀。扫描电镜(SEM)分析结果表明,混合菌体系中45钢腐蚀产物膜存在大量裂纹且金属表面点蚀现象更为严重。 The corrosion behavior of 45 steel under the synergistic action of Thiobacillus and Pseudomonas was studied by weight loss method, surface analysis technique and electrochemical testing technique. The results showed that compared with the single strain, the average corrosion rate of 45 steel was significantly inhibited by the mixture of the two kinds of bacteria at the initial stage of corrosion. With the prolongation of immersion time, the electrochemical impedance of the electrode decreased in the mixed system at 30 d, the corrosion potential decreased, the corrosion current density increased, and the mixed bacteria gradually accelerated the metal corrosion. Scanning electron microscopy (SEM) analysis showed that there were a large number of cracks in the corrosion product film of 45 steel in the mixed bacterial system and the pitting corrosion on the metal surface was more serious.