Microstructure and Performance of Nano-WC-10Co4Cr Coating for Piston Rod

Nano-WC-10Co4Cr ceramic coatings were prepared on the surface of piston rod by high-power high veloaty oxygen fuel (HVOF) thermal spraying technology. The surface properties of nano-WC-10Co4Cr ceramic piston rod were studied and analyzed by means of scanning electron microscope (SEM), metallographic analyzer, binding force tester, micro-hardness tester, and electrochemical workstation. The results showed that the nano-WC-10Co4Cr ceramic coating had much higher hardness and corrosion resistance than those of the piston rod substrate. After abrasion with silicon nitride balls at 500 g load for 180 min, the wear of the coating was less than 1/150 of the substrate, and the bonding strength between the coating and the substrate exceeded 80 MPa. The prepared nano-WC-10Co4Cr ceramic coatings completely meet the actual use requirements of the piston rod, and could greatly improve its service life.