碳钢与低合金钢耐大气腐蚀性研究

采用干湿复合循环实验、电化学交流阻抗和扫描电镜等方法研究了7种碳钢与低合金钢在试验环境中的腐蚀规律及腐蚀试验后带锈试样的电化学特征.结果表明，7种材料的腐蚀失重率随时间均遵从负指数规律：Y=Y0+Ae-t/B.电化学测试结果表明带锈试样进一步腐蚀的速度受阴极扩散过程所控制;7种材料带锈试样的阻抗值与材料的年腐蚀速率呈线性关系.

STUDY ON ATMOSPHERIC CORROSION OF LOW ALLOY STEEL

The corrosion of 7 kinds of mild steel and low alloy steelin immersion-wet-dry cycle test environment and the electrochemical feature of rusted metals after test were studied by using EIS and SEM et al.The solution containing HSO-3 and Cl-,was used for wetting and immersion specimens at circumstance emperature 40℃ for 4 min respectively.The drying cycle was maintained for 12 min at temperature 12℃.The results indicated that,the weight loss all followed exponential decay function:Y=Y0+Ae-t/B.The corrosion rate of mild steel was 2.49 times than that of the most corrosion resistant low alloy after 120 h test.The results of electrochemical measurement showed that,the further corrosion rate would be controlled by cathodic diffusion process.The impedance of 7 kinds of steels after corrosion test was linear with the annual corrosion rate.