Effect of CeO₂ Addition on Microstructure and Properties of High VelocityOxygen Fuel Sprayed Micro-Nano Structural WC-10Co4Cr Coating

The micro-nano structural WC-10Co4Cr coating and the micro-nano structural WC-10Co4Cr coating modified with 1wt% CeO₂ were prepared by high velocity oxygen fuel (HVOF) spraying. The effect of CeO₂ addition on the microstructure, mechanical properties and abrasive wear resistance was studied. The results show that the addition of CeO₂ inhibited the formation of Co₃W₃C phase during the powder sintering process, and reduced the content of W₂C phase during spraying. The porosity of the CeO₂ modified coating was 72% of that of the unmodified coating. The addition of CeO₂ increased the degree of chromium agglomeration, which was not conducive to the formation of CoCr bonding phase. The mechanical properties and abrasive wear resistance of the CeO₂ modified coating were lower than those of the unmodified coating, and the microhardness and fracture toughness were reduced by 11% and 7%, respectively. After wear for 15 600 r, the wear mass loss rate of the CeO₂ modified coating was 36% higher than that of the unmodified coating.