Direct cold spray deposition of Cu was not possible on carbon fiber-reinforced polymer composites (CFRPs) with thermosetting polymer as the matrix material due to substrate erosion. In a recent study, an epoxy-CFRP was successfully metallized through a hybrid coating process that involves three consecutive coating steps: (i) electroless deposition, followed by (ii) electrodeposition, and finally (iii) cold spray. In this present study, for the reduction of the coating process steps, a duplex metallic coating was developed on an epoxy-CFRPs by cold spray deposition of tin (Sn) to fabricate a continuous metallic interlayer, followed by Cu electrodeposition (i.e., SnCS-CuEP). The tensile adhesion bond strength and the electrical resistivity of the duplex coating were investigated. It was found that cold-sprayed Sn coating failed adhesively in the absence of the electrodeposited Cu coating. After the electrodeposition of Cu, cohesive failure of the cold-sprayed Sn coating took place. A “dissolution-deposition” mechanism has been established to explain the cohesive failure of the coldsprayed Sn coating after electrodeposition. The cohesive strength of the Sn coating is slightly higher than that of the previously fabricated three-step coating system. The electrical conductivity of the electrodeposited Cu coating was found to be 90% of bulk Cu. These results suggest that a duplex SnCS-CuEP coating can be fabricated on epoxy-CFRPs with relatively high electrical conductivity and slightly enhanced adhesion properties as compared to multilayered coatings fabricated using a three-step electroless deposition-electrodeposition-cold spray process.

Single component tin coatings have been successfully cold-sprayed onto carbon fiber reinforced polymers. Coatings with mixed metal powders have also been sprayed to improve conductivity for lightning strike protection purposes. Test results indicate a noticeable improvement in deposition efficiency with the addition of a secondary metallic powder. This study examines the effect of aluminum powder additions in tin coatings. Following cold spraying of various Sn-Al mixtures over a wide range of gas pressures, unusual coating morphologies were observed. The study of these morphologies reveals two distinct deposition phases depending on spray pressure. The presence of submicron particles also supports the occurrence of a powder melting phenomenon during the spraying process.

Babbitt surfacing is used in tribological applications because of its low friction coefficient. Thermal spray surfacing and pouring are two widely used production processes for Babbitted parts. This paper presents a comparative analysis of structures and friction properties of Sn-Sb-Cu Babbitt layers produced by these techniques. The sprayed Babbitt coatings were produced by arc spraying of 1.6 and 3 mm diameter wire.

Because of their characteristic spray geometry, pressure-gas-atomizers can be used to create thick coatings from molten metal. Production rates of pressure-gas-atomizers are substantially higher compared to conventional Thermal Spraying (100 – 200 kg/h based on molten tin). The shape of the spray cone can be designed by the geometry of the atomizer. The mean particle sizes and velocities (molten tin and tin-copper alloys) are controlled by the gas flow. Powder products and coatings of several millimeters on steel substrates were investigated. The average density of the layer was higher than 99%.

The spreading and solidification of a molten droplet is governed a number of factors such as fluid inertia, viscosity, surface tension, surface wettability, heat transfer between the droplet and substrate, and surface thermal properties. Most numerical and experimental studies of droplet impact have considered a single molten droplet landing on a flat, solid surface. This paper investigates the sequential deposition of tin droplets with their centers offset using a three-dimensional model of droplet impact and solidification. In this study, the successive deposition of two tin droplets on a stainless steel substrate is simulated and the results are compared with photographs of impacting droplets. Paper includes a German-language abstract.