Improvement of Wear Resistance of Laser-Clad Fe-Cr-Mo-B-C-(Tic) Amorphous-Nanocrystalline Coating

Abstract

Fe-base amorphous-nanocrystalline coating has attracted attention for its unique wear and corrosion resistance. Reinforcing phase has always been the dominating approach for improvement in wear resistance. In this paper, Fe-Cr-Mo-B-C amorphous powder with different content of TiC was adopted as the precursor for laser-clad coatings. The effects of TiC content on the microstructure, phase composition, hardness, composition distribution, and wear resistance of the coating were studied. The results show that the coatings are mainly composed of Fe 23 (C, B) 6 , Cr 23 C 6 , and TiC; Compared with the TiC-free coating, the addition of TiC lowered the micro hardness of the coating. With the increase of TiC, the micro hardness first rises and then falls with the highest value of coating #4 with 15% TiC up to 1209.30±115HV 0.05 . Coating #3 with 10% TiC possesses the lowest friction coefficient and wears volume, indicating the best wear resistance. The wear mechanism of the coatings was discussed according to the morphology of the wear trace, the energy spectrum composition (EDS) analysis, and X-ray photoelectron spectroscopy (XPS) results of the wear debris.

Keywords: Laser cladding, coating, amorphous, nanocrystalline coating, wear resistance