目的 研究KI和硫脲对月桂酰两性基二乙酸二钠的缓蚀增效作用。方法 首先以静态挂片失重法测定三乙醇胺、乙二胺四甲叉膦酸钠（EDTMPS）、月桂酰两性基二乙酸二钠（M）三种缓蚀剂的缓蚀性能，筛选出缓蚀效果最好的月桂酰两性基二乙酸二钠作为复合缓蚀剂的主要成分，然后对月桂酰两性基二乙酸二钠进行复配增效实验，并采用3D激光共聚焦显微镜对腐蚀过后的挂片表面形貌进行观察，采用EDS及SEM对挂片表面上形成的腐蚀产物膜进行表征。结果 当KI和月桂酰两性基二乙酸二钠的质量比为1:5时（M5K），缓蚀率提高了7%，腐蚀速率降低了0.0105 mm/a，缓蚀效果最佳；当硫脲与月桂酰两性基二乙酸二钠以1:10的比例进行复配时（M10S），缓蚀率提高5.8%，腐蚀速率降低0.0114 mm/a，此时的缓蚀效果略低于M5K。结论 在特定的比例下，KI和硫脲对月桂酰两性基二乙酸二钠的缓蚀性能均有一定的增效作用。KI是增加其吸附性能，而硫脲则是产生鳌合作用，这为两性咪唑啉的缓蚀性能增效研究提供了一定的参考。

The work aims to study synergetic effect of KI and thiourea on corrosion inhibition of disodium lauroamphodiacetate. Corrosion inhibition of corrosion inhibitors including triethanolamine, EDTMPS and disodium lauroamphodiacetate (M) was tested in static weight-loss method, respectively. Disodium lauroamphodiacetate which exhibited the optimal corrosion inhibition effect was selected as main ingredient of compound corrosion inhibitor. Then complex synergism experiment was performed to the disodium lauroamphodiacetate. Surface morphology of corroded steel slabs (Q235) was observed with a 3D laser confocal microscope, and corrosion product film on the steel slabs was characterized with SEM and X-ray energy dispersive spectrum (EDS). Inhibition rate increased by 7%, corrosion rate decreased by 0.0105 mm/a and corrosion inhibition effect was the best at the KI:M ratio of 1:5 (M5K). Inhibition rate increased by 5.8%, corrosion rate decreased by 0.0114 mm/a and corrosion inhibition effect was slightly inferior to that of M5K at the KI:M ratio of 1:10 (M10S). KI or thiourea have an excellent synergetic effect on corrosion inhibition of disodium lauroamphodiacetate at specific KI:M ratio. KI enhances its adsorption performance while thiourea has sequestration effect, which provides certain reference for the studying synergetic effect on corrosion inhibition of amphoteric imidazolines.