Abrasive Wear of HVOF Sprayed Cr3C2-NiCr Coating

The effects of oxygen flow, propane flow and spray distance on the microhardness and abrasive wear resistance of HVOF sprayed Cr3C2-NiCr coatings were studied. It is found that the coatings with comparatively higher microhardness were deposited in the spray conditions of the higher flow of propane, the moderate flow of oxygen and spray distance. The abrasive wear resistance of the coatings was significantly influenced by the flows of propane and oxygen. The coatings with lower abrasive wear weight loss were sprated in the lower flow of oxygen and moderate flow of propane. There was no evidint relationship between the microhardness and abrasive wear resistance. It was shown by the examination of worn surface that the cutting or gouging was the main feature of the coatings in the early stage of wear process. However, the abrasive wear of HVOF sprayed Cr3C2-NiCr coatings was dominated by the cracking and spalling of carbide particles in the coatings.