Microstructure and tribological behavior of cold-sprayed tin-bronze/quasicrystal composite coating

Tin-bronze and tin-bronze/quasicrystal composite coatings were prepared by cold spray process. Optic microscope (OM), scanning electron microscope (SEM) and microhardness tester were used to examine microstructures and microhardness of the prepared coatings. Dry sliding tribological tests of the coatings were conducted in an ambient atmosphere, and the wear mechanisms were discussed according to the worn traces investigation. The influences of an incorporation of particulate quasicrystalline phase on the microstructure and tribological behavior of reinforced composite coating were investigated. The results show that the composite coating prepared by cold spraying of mechanically blended powder presents a lower porosity and a higher microhardness as compared to the monolithic bronze coating. Hard quasicrystal particles exhibit a relatively lower deposition efficiencies, and the composite coating has a slightly lower coefficient of friction and a higher wear rate, as compared to the bronze coating. The abrasive wear is mainly responsible for the tribological behavior of the composite coating.