Hydroxyapatite (HA, Ca10(PO4)6(OH)2) composite coatings added the second phases could improve the mechanical properties and bonding strength. The cold spraying technique, as a technology for the deposition of solid particles at low temperatures, is employed to deposit HA ceramic composite coatings. Nano-HA material possesses the characteristics of enhancing properties and promoting interface bonding. Due to the exceptional mechanical properties of Ti material, adding Ti particles could improve the mechanical properties of nHA/Ti composite coatings. In order to explore the deposition deformation mechanism of composite particles under different cold spraying conditions, numerical simulation and experimental testing of deposition behaviors of dual nano HA/Ti composite particles were analyzed. As the particle velocity increased from 400 m/s to 800 m/s in the numerical simulation analysis, the higher the particle velocity, the more serious the deposition deformation. Meanwhile, more cracking and splashing phenomena occurred on the surface of the particle. By analyzing the stress value curve of Ti and HA units under different particle velocites, it can be revealed that the adiabatic shear instability phenomenon occurred during the particle depositing on the substrate. In addition, the degree of particle deformation increased with the decrease of the particle size. The results of the experimental investigation were consistent with that of the numerical simulation.

numerical simulation; experimental; cold spray; HA/Ti; deposition behaviour