Numerical Analysis of Deformation Behavior and Interface Bonding of Ti6Al4V Particle After Subsequent Impact During Cold Spraying

During cold-spraying processes, the deposited particles play a crucial role owing to the subsequent particle collisions with surface. Herein, using finite-element modeling, we numerically analyze the particle behavior under three models: impact of a single Ti6Al4V (TC4) particle, deposited particle hammered by a subsequent TC4 particle, and deposited particle impacted by a large shot peening particle (SP). For the single TC4 particle case, the particle deformation was limited and maximum interface temperature of the particle was lower than its melting point. The high-temperature region was mainly distributed in a limited area near the particle edge. Meanwhile, for subsequent impact in the second TC4 particle case, the upper half of previously deposited particle was deformed, although the change in maximum interface temperature was minimal. However, for particles subsequently impacted by large peening particle, the deformation of previously deposited TC4 particles increased significantly, and the temperature, both adjacent to and opposite the interface, exceeded the melting point of the titanium alloy in a large surface area, indicating that localized interfacial melting has occurred. In the third case, the change in interface temperature, stress, and energy with time, along with the experimental results, suggests that the bond between the particle and substrate enhanced.