目的 研究添加元素Zn含量的变化对涂层的显微组织、孔隙率、硬度及涂层-基体间界面结合强度等的影响规律。方法 采用冷喷涂技术在Q345R板材表面制备性能优良的纯Al和Al-Zn复合涂层，通过扫描电子显微镜对涂层的形貌进行分析，通过维氏显微硬度计对涂层的力学性能进行表征，并揭示涂层与基体间的界面结合机理。结果 冷喷涂纯Al和Al-Zn复合涂层与Q345R钢基体的结合良好，界面处无明显的孔洞及裂纹。随着Zn含量的增加，复合涂层的致密度、硬度逐渐提高;纯Al和Al-20wt.%Zn复合涂层的界面结合强度相当，且失效断裂形式为典型的界面粘结断裂。随着添加元素Zn含量的增加，涂层与基体间的界面结合强度逐渐增大，Al-40wt.%Zn涂层的结合强度为35 MPa，且断裂方式由界面粘着断裂转变为以界面粘着断裂为主、涂层内部粘聚断裂为辅的复合失效模式。结论 以低温固态沉积为特点的冷喷涂技术可有效避免氧化、相变、热裂等高温导致的不利影响，在沉积过程中，随着添加元素Zn含量的增加，对涂层的夯实作用不断加强，提高了涂层的致密性，从而使涂层的力学性能得到改善。

The effects of Zn content on the microstructure, porosity, hardness and interfacial bonding strength between coating and substrate were studied. Pure Al and Al-Zn composite coatings with excellent properties were prepared on Q345R plate by cold spraying technology, the morphology of the coating was analyzed by scanning electron microscope, the mechanical properties of the coating were characterized by Vickers microhardness tester, and the interface bonding mechanism between the coating and the substrate was revealed.The results show that the bonding between pure Al and Al-Zn composite coatings with Q345R steel substrate is well, without obvious holes and cracks at the interface. With the increase of Zn content, the density and hardness of the composite coating increase gradually, and the interfacial bonding strength of pure Al and Al-20wt.%Zn composite coating is similar, and the failure fracture mode is typical interfacial adhesive fracture. With the increase of the Zn content, the interfacial bonding strength between the coating and the substrate increases gradually, the bonding strength of Al-40wt.% Zn composite coating is 35 MPa, and the fracture mode changes from adhesive fracture to the mixed failure mode of dominant interfacial adhesive fracture and auxiliary cohesive fracture of the coating. In conclusion, cold spraying, characterized by low temperature solid state deposition, can effectively avoid the adverse effects such as oxidation, phase transition, and thermal cracking caused by high temperature. In the deposition process, with the increase of the Zn content, the tamping effect on the coating is constantly strengthened, which improves the compactness and the mechanical properties of the coating.