目的 考察一种新型的咪唑啉类缓蚀剂CPA-1对N80钢在CO2环境下的缓蚀性能。方法 通过失重法、电化学阻抗谱和极化曲线，研究了在不同温度下缓蚀率和缓蚀剂浓度之间的关系，利用扫描电子显微镜和扫描电化学显微镜对表面形貌进行了观察分析，根据等温吸附模型研究了咪唑啉缓蚀剂在N80钢表面的吸附类型。结果 失重结果表明，缓蚀剂的缓蚀效率随浓度的增大而升高，当温度为40 ℃、缓蚀剂质量浓度为250 mg/L时，缓蚀率达到95%；温度升高至80 ℃时，缓蚀率下降至87%。电化学试验表明，咪唑啉类缓蚀剂对阴极和阳极反应均有抑制作用。表面形貌分析表明，缓蚀剂能有效改善金属表面的腐蚀程度。结论 咪唑啉类缓蚀剂CPA-1属于混合型缓蚀剂，对N80钢具有较好的缓蚀性能。缓蚀机理为通过吸附方式在金属表面形成一层吸附膜抑制金属腐蚀，吸附方式遵循Langmuir吸附等温模型，物理吸附和化学吸附均会在金属表面发生。

The work aims to investigate corrosion inhibition effect of imdidazoline inhibitor CPA-1 on N80 steel in 3.5%NaCl solution saturated CO2. The relationship between inhibition efficiency and inhibitor concentration at different temperature was studied in the method of weight-loss, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. Surface morphology was observed and analyzed with scanning electron spectroscope (SEM) and scanning electrochemical spectroscope (SECM). Adsorption type of imidazoline inhibitor on the surface of N80 steel was studied based upon isothermal adsorption model. Weight-loss results showed that inhibition efficiency of imdidazoline inhibitor increased as inhibitor concentration increased, it reached 95% when the concentration was 250 mg/L at 40 ℃, and inhibition efficiency decreased to 87% slowly at 80 ℃. Electrochemical tests indicated that imdidazoline inhibitor could inhibit both catholic and anodic reaction. Surface morphology analysis showed that the corrosion inhibitor could improve corrosion degree of metal surface effectively. Imdidazoline inhibitor CPA-1 acts as a mixed-type corrosion inhibitor and exhibits good corrosion inhibition for N80 steel. Inhibition mechanism of imdidazoline inhibitor is to prevent metal corrosion by forming one layer of adsorption film on metal surface in the method of adsorption, and the absorption obeys Langmuir adsorption isotherm. Both physical adsorption and chemical adsorption are possible on metal surface.