Nickel-cobalt/silicon carbide(Ni-Co/SiC)composite coatings were fabricated by supergravity field-enhanced electrodeposition.The surface morphology and the distribution of the SiC particles in the coatings were examine...Nickel-cobalt/silicon carbide(Ni-Co/SiC)composite coatings were fabricated by supergravity field-enhanced electrodeposition.The surface morphology and the distribution of the SiC particles in the coatings were examined by scanning electron microscope and energy dispersive X-ray spectrometry.The preferred orientations of the coatings were measured by X-ray diffractometry.The wear resistance and microhardness were measured by a reciprocating tribometer and a microhardness instrument,respectively.The results revealed that the use of the supergravity field enhanced the smoothness of the as-deposited Ni-Co/SiC coatings,and the SiC nanoparticles were uniformly distributed in comparison with that for conventional electrodeposition.When the rotation speed of the cathode,which provided the supergravity field,was 800 r/min,the SiC content in the coating reached a maximum of 8.1 wt%,which was a much higher content than the 2.2 wt%value obtained under conventional electrodeposition.The highest coating microhardness of 680 HV was also observed at this rotation speed.In addition,the wear resistance of the as-prepared Ni-Co/SiC coatings exhibited improved performance relative to that prepared under normal gravity.A minimum wear weight loss of 1.4 mg together with an average friction coefficient of 0.13 were also realized at a rotation speed of 800 r/min,values which were much lower than those for normal gravity.展开更多
基金National Key Research and Development Program of China(Grant No.2018YFB1105900)National Basic Research Program of China(973 Program,Grant No.2015CB057502)Fundamental Research Funds for the Central Universities(Grant No.NZ2016106).
文摘Nickel-cobalt/silicon carbide(Ni-Co/SiC)composite coatings were fabricated by supergravity field-enhanced electrodeposition.The surface morphology and the distribution of the SiC particles in the coatings were examined by scanning electron microscope and energy dispersive X-ray spectrometry.The preferred orientations of the coatings were measured by X-ray diffractometry.The wear resistance and microhardness were measured by a reciprocating tribometer and a microhardness instrument,respectively.The results revealed that the use of the supergravity field enhanced the smoothness of the as-deposited Ni-Co/SiC coatings,and the SiC nanoparticles were uniformly distributed in comparison with that for conventional electrodeposition.When the rotation speed of the cathode,which provided the supergravity field,was 800 r/min,the SiC content in the coating reached a maximum of 8.1 wt%,which was a much higher content than the 2.2 wt%value obtained under conventional electrodeposition.The highest coating microhardness of 680 HV was also observed at this rotation speed.In addition,the wear resistance of the as-prepared Ni-Co/SiC coatings exhibited improved performance relative to that prepared under normal gravity.A minimum wear weight loss of 1.4 mg together with an average friction coefficient of 0.13 were also realized at a rotation speed of 800 r/min,values which were much lower than those for normal gravity.
