Structure and tribological properties of argon arc cladding Ni-based nanocrystalline coatings

TiN-TiB2 nanocrystalline coatings have been in-situ synthesized on the 35CrMnSi steel surface by argon arc cladding process under different welding technological parameters. The calculating method was established for the analysis and calculation of the dilution ratio. The microstructures of the nanocrystalline coatings were characterized by means of X-ray diffraction meter(XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM).Results indicated that the phase of coatings were TiN、TiB2、TiB、Cr23C6 and γ-Ni. The welding technological parameters of nanocrystalline coatings have certain effects on the dilution ratio of the clad layer. The tribological behavior of both the substrate and the coatings was investigated in detail. An average microhardness of 1420HV0.5 was obtained with a cladding current of 120A. While the nanocrystalline coatings shows better wear resistance properties than 35CrMnSi steel.