Simulation of Cold Spray Particle Deposition Process

This thesis presents a comprehensive simulation of the cold spray particle deposition process, focusing on the mechanics of particle impacts and their resultant effects on substrate materials. The objective was to analyze and predict fracture modes including tensile and shear failures induced by multiple particle impacts. Using a computational approach, we delineated four critical steps in the crack propagation process: void formation, crack formation, crack growth, and eventual coalescence leading to failure. Insights from the simulations revealed that tensile failures predominantly occurred beneath substrate surfaces and around crater peripheries, while shear failures were primarily located at crater surfaces. A predictive criterion equation was established, correlating erosion velocity, contact angles, and other physical parameters, which aids in understanding damage initiation. Notably, the equivalent plastic strain threshold for damage onset in copper was identified as 1.042. These findings contribute valuable knowledge towards optimizing cold spray processes and enhancing material performance under high-impact conditions.