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Using Cu-Zn mixed powder as spray powder, Cu-Zn composite coating was prepared on 1Cr13 substrate by low-pressure cold spray technique. The composite coating was annealed at different annealing temperatures, and then the mechanical properties of the coating were tested. Observing the micrographs and testing hardness of composite coatings before and after annealing heat treatment by X-ray diffractometer, field emission scanning electron microscope and microhardness tester. The results show that the copper-zinc composite coatings are dense and the coatings are tightly bonded to the substrate; When the copper-zinc composite coatings are annealed between 200 °C and 300 °C, the metal particles interfaces in the coatings are obvious, and intermetallic compounds are formed in the coatings, such as β(CuZn) and γ(Cu5Zn8). When the annealing temperature is 200 °C, the hardness of copper-zinc composite coating reaches the highest (157.8HV), and the bonding strength reaches the lowest (7.5MPa); When the copper-zinc composite coatings are annealed between 350 °C and 450 °C, the metal particles interfaces in the coatings are not obvious; When the annealing temperature is 450 °C, the hardness of copper-zinc composite coating reaches the lowest (102.4HV), and the bonding strength reaches the highest (13.9MPa).