Finite Element Modeling and Analysis of Ceramic Particle/Substrate Interface Fracture Evolution and Particle Retention at Varying Impact Velocities in Cold Spray

Abstract

A finite element (FE) model of a 25-µm Al₂O₃ particle impacting an AISI 1018 steel surface is constructed using the Johnson–Holmquist-2 and Johnson–Cook material definition models, respectively. Particle impact velocities in the range of 200–700 m/sec, obtained using a deLaval nozzle, are considered. Energy, temperature, and strain evolutions over time for varying impact velocities are reported, along with penetration depth into target material. Penetration results are validated against experiments, showing good agreement, with observed depths between 4.8 and 8.2 µm. Penetration, contact pressure, and contact time for varying impact velocities are predicted, along with their effects on the interfacial bonding mechanism between particle and substrate. The threshold velocity for Al₂O₃ particle fragmentation is estimated at 170 m/sec. The stress behavior and the location of failure onset within the particle are predicted and described. The damage and fragmentation behavior of Al₂O₂ particles of different sizes is also analyzed. The implications of obtained results for cold spray deposition of metal matrix composite material are discussed.