采用极化曲线法研究了缓蚀剂MJ对N80钢在硫离子介质中的缓蚀作用及缓蚀机理。结果表明:20 ℃下，不添加MJ时，随着硫离子含量的增大，腐蚀速率先增大后减小，硫离子质量浓度为100 mg/L时腐蚀速率最大；在硫离子质量浓度为200 mg/L的水溶液中加入MJ后，腐蚀速率明显下降，当MJ质量浓度为150 mg/L时，缓蚀率可达81.9%，缓蚀效果明显优于市售缓蚀剂；MJ能使碳钢的腐蚀反应活化能升高，腐蚀速率明显下降，同时其在碳钢表面的吸附符合Langmuir吸附规律。

The inhibitive behavior and mechanism of corrosion inhibitor MJ on N80 steel in sulfide medium were studied by polarization curves. The results showed that when MJ was not added in sulfide medium at 20 ℃, with the increase of sulfide content, the corrosion rate first increased and then decreased, the corrosion rate reached maximum when the concentration of sulfide was 100 mg/L. After adding MJ into 200 mg/L sulfide solution, the corrosion rate decreased significantly, the inhibition efficiency of MJ was up to 81.9% when the concentration of MJ was 150 mg/L. The inhibition efficiency of MJ is obviously higher than that of commercial corrosion inhibitors. MJ can also increase the activation energy of corrosion reaction, which results in a decrease of corrosion rate. Its absorbance behavior can be expressed by the equation of Langmuir model.