Cold spray (CS) technology has proven an enormous potential in the production of composite coatings, enabling a production of materials with superior qualities such as enhanced tribological behavior. This study aims to investigate the tribological properties of CS Al-based composite coatings reinforced by quasicrystalline (QC) particles. Two different Al alloys were used as the matrix, AA 6061 and AA 2024, and mixed with Al-based QC particles (Al-Cr-Fe-Cu) at different Al/QC ratios. A room-temperature ball-on-disc test was then used to evaluate the wear resistance of the CS composite coatings in air and compared to those of the CS non-reinforced Al alloy coatings as well as cast counterparts (AA 6061-T6). We have demonstrated that CS could be employed to produce dense and thick Al-QC composites. Further, the addition of the QC particles into the structure increased the wear resistance of the matrix resistance up to 8 times.

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.