NbC coatings, 250 urn thick, were deposited by low-velocity flame spray on AISI 304L steel substrates and were further remelted using a 400 W Yerba fiber laser (IPG Photonics, model YLR), in a chamber (model MB 200 Modular MBraun)with a controlled argon atmosphere. For the selection of the transverse parameters, isolated passes with transverse of the coatings were performed using three focal lengths (DF) (-1, 0 and +1) and three transverse speeds (Vr) of 10, 15 and 20 mm / min. Using the selected laser parameters, layers were recast with 8 passes and 10% superposition. Erosion-corrosion tests were performed in a solution of 3.5% NaCl in distilled water with 300 g of SiC. Surfaces and cross-sections of the coatings were characterized by optical microscopy (OM), scanning electron microscopy (SEM) with dispersive energy microanalysis (EDS), and x-ray diffraction. Microhardness measurements were performed in the cross section of the coatings. Modified surfaces of dense 800 μm thick coatings, with no defects (pores, voids, microcracks, and microstructural heterogeneity) and excellent metallurgical bonding with the substrate, were obtained. It was found that the dilution of the coating with the substrate formed a gradient of chemical composition and mechanical properties. The erosive-corrosive wear resistance of the laser remelted coatings was higher for the eroding angle of 90°.
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