Wear behaviors of 5 wt % SiO2?Ni60 coatings deposited by atmospheric plasma spraying under dry and water-lubrication sliding conditions

NiCrBSi alloys have a huge potential for applications in the field of various industries due to their high hardness and excellent wear resistance performance. In this experiment, the wear behaviors of the plasma-sprayed Ni60 and 5 wt % SiO2?Ni60 composite coatings under dry and water-lubrication sliding conditions were comparatively investigated utilizing a ball-on-disk tribometer at room temperature. Furthermore, the phase compositions and worn tracks of the two as-sprayed coatings before and after the friction test were inspected through X-ray diffraction and scanning electron microscopy to demonstrate the main wear mechanisms of both coatings. And the results manifested that the incorporating of the SiO2 nanoparticles into Ni60 alloy played a critical effect on improving the wear-resistance performance of the 5 wt % SiO2?Ni60 composite coating, especially under the water-lubrication sliding condition. The reason was found to be the filling and polishing effect of nanoparticles, together with the cooling and water lubrication effect of deionized water, in the course of friction test. Moreover, the model diagram of the wear behaviors of the 5 wt % SiO2?Ni60 composite coating was also established to comprehensively analyze the stress of nanoparticles during friction.