Effects of Y2O3 Content on Wear Resistance and Corrosion Resistance of 316L/TiC Coating Fabricated by Laser Cladding

Abstract

Laser cladding technology is a surface modification technology emerging in recent years, and it is widely used in the marine engineering field. Since the structural steels used in marine engineering are mostly carbon steels, their wear resistance and corrosion resistance are poor. In this paper, 316 L stainless steel/TiC composite coatings with different Y2O3 addition amounts were fabricated on Q355B steel surface using the laser cladding technology, and the phase composition, microstructure, microhardness, wear resistance, and corrosion resistance of the coatings were investigated with an X-ray diffractometer (XRD), a scanning electron microscope (SEM), a digital microhardness tester, a friction and wear tester, and an electrochemical workstation. When Y2O3 is added, the crystals in the bottom part of the coating are basically broken and the organisation becomes more dense. When the Y2O3 addition amount is 2%, the hardness is highest, the frictional coefficient curve of the coating exhibits a stable descending trend, and the coating mass loss is the lowest. When Y2O3 is added at 1%, the dynamic potential polarisation curve shows high corrosion potential and low corrosion current density and exhibited the best performance in EIS. The added Y2O3 evidently improves the wear resistance and corrosion resistance of 316 L stainless steel/TiC composite coatings, and this provides a new possibility that a composite coating modified with rare earth oxide is used for repair of marine engineering structures.