Numerical Investigation of Particles in Warm-Particle Peening-Assisted High-Velocity Oxygen Fuel (WPPA-HVOF) Spraying

摘要

Shot peening was induced by utilizing the particles that flow out of the nozzle in a WPPA-HVOF process. For investigation of the peening particles, a model was built to simulate the HVOF spraying process including the temperature, velocity, pressure field of the flame, and the reaction of kerosene oxidation. The effect of incident velocity, incident position, and the diameter on the in-flight particle was presented. Incident velocity is an important factor for the synchronization of shot peening and coating deposition. The critical velocity was introduced to describe the particle state after hitting onto the substrate. The velocity and temperature of small particles injected in the barrel were measured experimentally to verify the model reliability. Experimental results reveal that the particle injected in the barrel deposited onto the substrate and the particle injected out of the nozzle rebounded, which agrees well with the predicted result.