Effects of C₂H₂ Flow Rate on Microstructure and Property of Multi-arc Ion Plated CrCN Coating

CrCN coating was deposited on surface of SKD11 die steel by multi-arc ion plating technique at different C₂H₂ flow rates (75,125,200,400 mL·min^-1). The effects of C₂H₂ flow rate on microstructure, hardness, bonding property, friction and wear behavior of the coating were studied. The results show that with C₂H₂ flow rate increasing, the surface roughness and thickness of the coating increased first and then decreased, and the hardness and adhesion strength decreased. When the C₂H₂ flow rate was relatively low, the CrCN coating had good ability to remove abrasive debris. When the C₂H₂ flow rate increased to 400 mL·min^-1, layered cracks appeared in the coating. The wear mechanisms of the coatings were slight abrasive wear and adhesive wear.