A Modeling Study of Bonding Mechanisms Between Similar and Dissimilar Materials in Cold Spraying on Polymeric Substrates

The potentials of the cold spray process, as novel manufacturing technology, are yet to be fully explored in the area of polymeric materials. In the present study, the mechanisms of the single-particle impact on polymeric substrates during the cold spraying are examined. The analyses are based on a finite element modeling framework that explores some of the fundamental mechanisms associated with the cold spray of similar and dissimilar particles on polyether ether ketone (PEEK) substrates. PEEK, Acrylonitrile Butadiene Styrene (ABS), and copper are used as particle materials due to their relative deformability with respect to the substrate. Each particle–substrate pair is analyzed at various temperatures and impact velocity conditions. Deposition of polymeric particles is analyzed at room temperature, temperatures slightly below and above their glass transition temperature. Cold spraying of copper particles on PEEK substrates is analyzed at temperatures ranging from room 22-230 °C. Our results suggest that the bonding mechanism is dependent on relative deformability of particle and substrate. PEEK and ABS particles on PEEK are governed by severe plastic deformation and shear instability, whereas the deposition of copper on PEEK occurs mainly by a mechanical anchoring process. The impact velocity and temperature conditions that are most likely to lead to successful deposition in each case are discussed.