Enhancing the (FeMnCrNiCo + TiC) cladding layer by in-situ laser remelting

Abstract

In this study, the (FeMnCrNiCo + 20%TiC) laser cladding layer was re-treated through multiple-pass in-situ laser remelting. Optical microscopy, scanning electron microscopy, and X-ray diffraction were used to analyse the evolution of microstructures and phases before and after the in-situ laser remelting processes. The micro-hardness and wear resistance of the composite coatings were systematically investigated using micro-hardness and abrasion. Results show that in-situ laser remelting decreased the dilution rate. The thermal effect of laser melting and the Maragni action in the liquid coating metal enabled the large-sized and loosened ceramic particles to remelt into the cladding layers. As a result, the ceramic particles in the cladding layers after in-situ laser remelting were modified considerably in terms of their spherification rate, dimension uniformity, and particle distribution. The weak spots caused by stress on the surfaces of the cladding layers were reduced, and accordingly the wear resistances improved.