Effect of WC-17Co content on microstructure, mechanical properties and tribological behavior of low-pressure cold sprayed tin bronze composite coating

As an important anti-wear material, tin bronze coatings and their composites have been widely used as bimetallic bearings, sliding plates and ship propellers. In this work, the dense CuSn10/WC-17Co composite coatings were deposited by low-pressure cold spraying (LPCS) technology. The effect of WC-17Co cermet content on the microstructure, mechanical properties and tribological behavior of the LPCS CuSn10/WC-17Co coatings was investigated. The results showed that the deformation of the particles that deposited inside the coatings was enhanced by the increasing peening effect of the WC-17Co cermet in feedstock powders. During the coating deposition process, the cold spraying can effectively avoid the decomposition or oxidation of the feedstock powders. Meanwhile, in the wake of the increasing WC-17Co content in the coatings, the hardness and bonding strength of the composite coatings were improved. In addition, the evolution of the coating fracture surfaces was analyzed. It is gratifying that the wear rate of the CuSn10/WC-17Co composite coating was significantly decreased to 3.75 x 10(-5) mm(3)/N.m. Correspondingly, the wear mechanisms of the coatings were all elucidated, respectively.