目的 提高Zn-Ni合金镀层的耐微生物腐蚀性能。方法 在硫酸盐电镀液中添加梯度浓度的4,5-二氯-N-辛基-4-异噻唑啉-3-酮（DCOIT），利用恒电流沉积方法，在碳钢表面阴极电沉积获得DCOIT复合Zn-Ni合金镀层。通过电沉积电位监测与电流效率计算评价DCOIT对电沉积过程的影响，利用扫描电子显微镜、电子能谱、X射线晶体衍射等研究DCOIT对Zn-Ni复合镀层形貌、结构与Ni含量的影响，使用傅里叶红外吸收光谱和荧光显微观察法验证DCOIT的成功复合及复合镀层的抗菌性能，最后将DCOIT复合Zn-Ni合金镀层暴露于硫酸盐还原菌（SRB）中，监测菌液的pH与菌体浓度，同时计算镀层的腐蚀速率，并观察镀层的腐蚀形貌，评价复合镀层的耐SRB腐蚀性能。结果 DCOIT在电沉积过程中会吸附在沉积表面，造成沉积电位负移，并略微降低了电流效率。DCOIT的添加显著改变了复合镀层的形貌、结构与Ni含量，其Ni含量与DCOIT的添加量呈线性增长关系，导致其晶体结构转变。DCOIT以有效形式存在于复合Zn-Ni合金镀层中，并显示出抗菌性能，DCOIT添加量为2 mmol/L时，镀层中的复合量最高，抗菌性能最好。最后，DCOIT复合Zn-Ni合金镀层能有效抑制环境中SRB的生长与代谢，自身腐蚀速率减慢，耐蚀性能明显增强。结论 DCOIT能够以有效形式复合于Zn-Ni合金镀层内部，并有效提高了镀层的抗菌性能，使其获得增强的耐SRB腐蚀性能。

The work aims to improve the microbiological influenced corrosion resistance of Zn-Ni alloy coatings. 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one (DCOIT) was added into sulfate electrolyte. DCOIT composited Zn-Ni alloy coatings were obtained on carbon steel by cathodic galvanostatic electrodeposition. By potential monitoring and current efficiency calculation, the influence of DCOIT on electrodeposition was evaluated. Further, scanning electron microscopy, energy- di-spersive X-ray spectroscopy and X-ray diffraction were performed to study the effect of DCOIT on morphologies, structures and Ni contents of the composited Zn-Ni alloy coatings. Then, the Fourier transform infrared spectroscopy and fluorescence mi-croscopy observation were used to verify the existence of DCOIT and the antibacterial effect of the composite coatings. At last, the pH and bacterial concentration variations were monitored by exposing the DCOIT composite Zn-Ni alloy coatings in sul-fate-reducing bacterial (SRB) medium and the corrosion rates of the coatings were calculated to evaluate the corrosion resistance of coatings in SRB medium. During the electrodepositing process, DCOIT was absorbed on the depositing surfaces, which led to negative electrodepositing potential shifts and decreased current efficiency. The addition of DCOIT dramatically influenced the morphology, structure and Ni contents of the coatings. The Ni content showed a linear growth relationship with the DCOIT adding concentration, leading to crystalline phase transformation. After electrodepositing, DCOIT existed in the composite coatings with effective molecular structure and showed antibacterial properties successfully. When 2 mmol/L DCOIT was added, the coating showed the largest compound quantity and the best antibacterial properties. Finally, the DCOIT composite Zn-Ni alloy coatings effectively inhibited the growth and metabolism of SRB, thus reducing corrosion rates and enhancing corrosion resistance. DCOIT can be successfully composited into Zn-Ni alloy coating, which effectively improves antibacterial properties and enhances corrosion resistance in SRB medium.