Optimizing mechanical and tribological properties of DLC/Cr3C2-NiCr duplex coating via tailoring interlayer thickness

A top DLC film was deposited on the surface of Cr3C2-NiCr coated 38CrMoAl steel substrate, and the effect of Cr3C2-NiCr cermet interlayer thickness on the mechanical and tribological properties of the duplex coating was investigated by experimental analysis and finite element modeling (FEM). Results shown that, compared with single DLC film, the load-bearing capacity and tribological performance of DLC/Cr3C2-NiCr duplex coating were significantly improved, especially its anti-wear performance was nearly ten times higher than that of the single DLC film. Moreover, the duplex coating with an optimum cermet interlayer thickness of 100 mu m showed the best comprehensive performance. FEM analysis also shown that the presence of Cr3C2-NiCr cermet interlayer limited the stress concentration area within the interlayer, which made the stress concentration area far away from the interface of DLC film and cermet interlayer, thus improved duplex coating durability. What's more, the cermet interlayer thickness increase resulted in the contact stress on DLC film increase, which contributed to the improvement of its tribological performance.

Automated summary

The effect of Cr3C2-NiCr cermet interlayer thickness on the mechanical and tribological properties of the duplex coating was investigated. Results showed that the load-bearing capacity and tribological performance of the duplex coating were significantly improved compared to the single DLC film, especially the anti-wear performance. The duplex coating with an optimum cermet interlayer thickness of 100 μm showed the best comprehensive performance.