目的 在中碳钢表面制备金属+氮化物涂层以研究其在腐蚀、磨损耦合环境下的服役行为。方法 利用电弧离子镀技术在42CrMo钢基体表面制备NiCoCrAlY/NiCoCrAlYN双层涂层，通过改变氮气流量来调控涂层中氮元素含量。采用显微硬度计以及特制的腐蚀磨损试验机，同时结合XRD、XPS、SEM等各类表征技术研究涂层力学及腐蚀磨损行为。结果 NiCoCrAlYN涂层物相主要为γ-Ni、γ‘-Ni3Al、fcc-CrN和fcc-AlN。随着N2流量的逐步引入，涂层中CrN/AlN陶瓷相含量增加，显微硬度从575HV0.05逐渐提升至730HV0.05，而结合力等级从HF 2下降至HF 3。NiCoCrAlY/NiCoCrAlYN双层涂层比NiCoCrAlY单层涂层具有更佳的腐蚀磨损性能，且随着N含量的增加而显著提升。当N2流量为400 mL/min时，涂层显示出最佳的腐蚀磨损性能。此外，涂层的失效形式也由磨损失效逐渐转变为腐蚀失效。结论 由于氮化物表层的高硬度特性增强了涂层耐磨性，NiCoCrAlY-NiCoCrAlYN界面的阻挡作用提高了涂层耐蚀性，加之底部NiCoCrAlY层具有良好的韧性和延展性，三者的综合作用导致NiCoCrAlY/NiCoCrAlYN双层涂层的腐蚀磨损性能优于NiCoCrAlY单层涂层。

The work aims to fabricate metal plus nitride hard coatings on medium carbon steel substrates to study the service behaviors under the corrosive wear conditions. NiCoCrAlY/NiCoCrAlYN double layer coatings were fabricated on 42CrMo steel substrates by means of arc ion plating. The nitrogen content was manipulated by varying the nitrogen gas flow. The mechanical and corrosive wear behaviors were studied with microhardness tester and tailored corrosive wear apparatus, in combination with multiple analytical techniques such as XRD, XPS and SEM. The results showed that NiCoCrAlYN coatings were mainly composed of γ-Ni, γ‘-Ni3Al, fcc-CrN and fcc-AlN ceramic phases. With the increase of N2 flow rates, the contents of ceramic phases increased, followed by the promotion of the coating micorhardness from 575HV0.05 to 730HV0.05, as well as the degradation of the coating adhesion from HF 2 to HF 3. Compared with the NiCoCrAlY single layer coating, the NiCoCrAlY/NiCoCrAlYN double layer coatings exhibited better corrosive wear performance, which was increased with the increase of N flow rates. The coating revealed the best corrosive wear resistance when the N2 flow rate reached 400 mL/min. Moreover, the failure model of coating also converted from wear failure to corrosion failure. The nitride surface with the virtue of high hardness improves the coating wear resistance, and NiCoCrAlY-NiCoCrAlYN interface increases the coating corrosion resistance as a result of interface barrier effect. In addition, the NiCoCrAlY bottom layer exhibits excellent toughness and malleability. Because of the three effects mentioned above, the corrosive wear resistance of NiCoCrAlY/NiCoCrAlYN double layer coatings is significantly higher than that of NiCoCrAlY single layer coating.