Interface Material Mixing Formed by the Deposition of Copper on Aluminum by Means of the Cold Spray Process

Development of Sustainable Cold Spray Coatings and 3D Additive Manufacturing Components for Repair/Manufacturing Applications: A Critical Review

“…According to adiabatic shear instability theory when a particle impacts in cold spray, the particle/particle or the particle/substrate interfacial areas experience an extensive localized deformation (i.e., shear deformation) during impact which leads to disruption/instability of the thin oxide surface films. This empowers an intimate conformal contact between the particle and the substrate or the previous deposited layer, and thus forms bonding [28][29][30][31]. Better illustration of this theory can be understood with the help of the following points: (1) plastic strain energy from the collision is retained in the system as heat increases the temperature of the substrate and softens the material.…”

“…The induction time (also known as "incubation time") represents the time between the beginning of surface treatment by the flow of particles and the beginning of particle adhesion to the surface. Induction time (deposition delay) vs. mean particle velocity of aluminum particle on polished Cu substrate [31]. Induction time (deposition delay) vs. mean particle velocity of aluminum particle on polished Cu substrate [31].…”

“…Induction time (deposition delay) vs. mean particle velocity of aluminum particle on polished Cu substrate [31]. Induction time (deposition delay) vs. mean particle velocity of aluminum particle on polished Cu substrate [31]. From Figure 7, the induction time is further segmented into three distinct zones (i.e., Section-I, -II, and -III) of interaction between particle and substrate, in account of two different particle velocities, v cr1 and v cr2 .…”

“…Furthermore, there is a least amount of particle velocity needed to accomplish the impact nature of bonding, since an adequate amount of mechanical/kinetic energy is requisite to plastically deform the solid particles [30]. Figure 6 further shows the presence of material adjacent to the interface behaving like a viscous fluid, resulting in the formation of interfacial waves, roll-ups, and vortices [31], in which the impact of a 20 μm spherical copper particle on an aluminum substrate was recorded at a particle velocity of 650 m/s. Particle bonding in cold gas spraying can be affected by numerous factors connected to geometrical parameters of the substrate, e.g., contact surface area, the depth and width of crater, and factors associated with thermomechanical parameters, including plastic strain, flow stress, pressure, and temperature at the interface.…”

Rebuilding the Transatlantic Partnership: US-EU Relations in the Post-Iraq Era

“…Calculated particle velocities are verified experimentally by means of a dual-slit, laser velocimeter. An empirical relationship of the penetration of micrometeorites into spacecraft skin is used to model the interface between the deposit and the substrate, and an empirical relationship between particle characteristics and critical velocity is used to model deposition efficiency (9).…”