Effect of ultrasonic power and pulse-on time on the particle content and mechanical property of Co-Cr3C2 composite coatings by jet electrodeposition

In order to obtain metal matrix composite coating with high content of particles by selective electrodeposition, pulsed ultrasonic was introduced to prepare Co-Cr3C2 composite coatings by jet electrodeposition. The effects of ultrasonic power and pulse-on time on the microstructure and mechanical properties of composite coatings were investigated. The morphology of the coatings was observed by scanning electron microscopy, and the content of chromium in the coating was measured by EDS spectrometer. The coating hardness was measured by a micro-hardness tester, and the friction coefficient was evaluated by a tribotester. The results show that both the power and the mode of the ultrasonic had a significant influence on composite codeposition. With the optimized deposition parameters, the Co-Cr3C2 composite coating containing > 30% Cr3C2 particles was obtained, which yields the highest hardness and the lowest friction coefficient.