Cold Spray Process for Co-Deposition of Copper and Aluminum Particles

Mixed-particle spraying has been applied to various aspects of industrial cold spraying for a long time. Due to the complexity of mixed-particle simulations, most studies only consider dozens of particles when considering particle collisions. This paper combines computational fluid dynamics and a discrete element method to analyze the entire trajectories of mixed particles. With simulations involving over one hundred thousand particles, we accurately tracked the three-dimensional positions and velocities of each particle, effectively visualizing their journey from feeder to substrate. By comparing the particles' velocities to their critical velocities, we could directly assess the deposition efficiency, achieving a comprehensive and accurate simulation of the complete cold spray process. The numerical model was validated using a multi-experimental analysis. The particle distribution and deposition area from the numerical model matched well with the experimental data. It was found that the mutual collision of copper and aluminum particles increased the number of copper particles, surpassing the critical velocity in the mixed powder by 24.2%. When copper particles and aluminum particles collided, the displacement of aluminum particles was more than three times that of copper particles in the direction perpendicular to the jet. This collision caused the aluminum particles to be more dispersed.

Automated summary

In this study, the entire trajectories of mixed particles in industrial cold spraying were analyzed using a combination of computational fluid dynamics and a discrete element method. The positions and velocities of each particle were accurately tracked, and a comprehensive simulation of the complete cold spray process was achieved. The numerical model was validated using experimental analysis, and the influence of the mutual collision of copper and aluminum particles on spray deposition was investigated.