Simulation of Particle Interaction with Surface Microdefects during Cold Gas-Dynamic Spraying

The cold gas-dynamic spray (CGDS) technique is utilized for repairing processes of a large number of metallic components in mechanical and process engineering, such as bridges or vehicles. Fine particles impacting on the component surface can be severely deformed and penetrate into the defects, filling and coating them, resulting in possible protection against corrosion or crack propagation. This work focuses on the investigation of the impact behavior of cold sprayed particles with the wall surface having microdefects in the form of cavities. The collision of fine single particles with the substrate, both made from AISI 1045 steel, was simulated with the finite element method (FEM) using the Johnson–Cook failure model. The impact phenomena of particles on different microdefect geometries were obtained and compared with the collision on a smooth surface. The particle diameter and defect were varied to investigate the influence of the size on the deformation behaviour. The different impact scenarios result in different temperature and stress distributions in the contact zone, penetration and deformation behavior during the collision.