The Effect of Primary Carbide on the Wear Resistance of Fe-Cr-C Coatings

The wear-resistant Fe-Cr-C coating has been widely used in industrial production owing to its high hardness and good comprehensive performance. Its anti-wear ability is mainly owing to the primary chromium carbides solidified during welding. In this study the effect of carbide morphology and distribution on the wear resistance of Fe-Cr-C coatings was investigated through experiment and simulation. In experiments, 3D microstructures of the typical carbides were examined using a high-resolution 3D X-ray computed tomography, and the 3D structures were then used in finite element simulation. Coatings with different morphologies and distributions of primary carbides were investigated. The results show that the fascicular primary chromium carbides break by the shearing stress during wear, leading to transverse fractures, while the mutual support among the homogeneous carbides contributes to the resistance of contact stress of the entire supporting framework, thereby imparting excellent wear resistance. Furthermore, the simulation results from the real 3D microstructure are consistent with the experimental ones. The fascicular structure produces a localized higher strain and larger stress concentration than the homogeneous one, implying higher abrasion loss in the former. These results will be helpful to optimize the structure design and final performance of the anti-wear Fe-Cr-C coatings. It will also be a new application of real-structure FE analysis in the widely used coatings for mining machines.