目的 研究 300M 高强钢表面的冷喷涂锌镍复合涂层的涂层性能。 方法 采用机械混合的方式将锌粉和镍粉进行混合，利用低温气动喷涂技术在 300M 高强钢表面制备锌镍复合涂层，采用扫描电子显微镜、能量色散谱和显微硬度测试仪研究涂层的微观组织结构。采用普通中性盐雾加速实验、涂层破损盐雾加速试验及户外暴晒试验，对冷喷涂锌镍涂层的抗腐蚀性能进行综合评价。考核冷喷涂对300M 钢基材疲劳性能的影响。结果 根据 SEM 的表面及截面图片分析，冷喷涂锌镍复合涂层十分致密，且无孔隙及裂纹，涂层的孔隙率平均为 0.4%，结合强度 40 MPa 左右。根据 EDS 结果分析，锌镍复合涂层中锌的质量分数为 85%左右，镍的质量分数为 15%左右。锌镍复合涂层的显微硬度为 70.8HV0.49。锌镍复合涂层中镍粒子的强化作用，提高了涂层的硬度。冷喷涂锌镍复合涂层具有非常好的抗腐蚀性能，盐雾实验超过 770 h，即使涂层破损也可以达到 600 h。户外暴晒实验 12 个月表面无明显腐蚀，并且冷喷涂对 300M 钢基材的疲劳性能没有影响。 结论 冷喷涂锌镍复合涂层作为抗腐蚀涂层，可以对300M 高强钢提供保护。

Objective To study the performance of Zn/Ni composite coatings on 300M high-strength steel surface, which were deposited by cold gas dynamic spray. Methods The coating was sprayed by Zn and Ni physical mixture powder on 300M high-strength steel surface. The morphology and microstructure of the coatings were analyzed by the SEM images, EDS and microhardness tester. The corrosion resistance of Zn/Ni coatings was comprehensively investigated by neutral salt-spray test, coating furcated test and atmospheric exposure test. The effect of cold spray on the fatigue property of 300M steel substrate was tested. Results The surface and cross-section SEM images indicated that the cold sprayed Zn/Ni composite coatings were very compact, without pores and cracks, the porosity of Zn/Ni coatings was 0.4% and the bonding strength was 40 MPa. The EDS analysis result showed that the mass fractions of Zn and Ni in the Zn/Ni composite coatings were about 85% and 15%, respectively. The microhardness of Zn/Ni coatings was 70.8HV0.49, this is because the hardness of the coatings was improved by the strengthening effect of Ni in the Zn/Ni coatings. Cold sprayed Zn/Ni composite coatings had very good corrosion resistance. The salt spray result of Zn/Ni coatings could reach 770 h, and it could reach 600 h even at coatings failure. No obvious corrosion was observed on the surface after 12-month atmospheric exposure test, and cold spray had no influence on the fatigue property of 300M steel substrate. Conclusion Cold sprayed Zn/Ni composite coatings could be used as efficient corrosion-resistant coatings on 300M high strength steel surfaces.