The influence of turning and burnishing on corrosion resistance of laser cladded Fe–Cr–Ni layer from viewpoints of thermodynamics and kinetics

Laser cladding is commonly used to improve the wear and corrosion resistance of the substrate material. However, mechanical machining is necessary, because the surface irregularities and poor surface roughness after laser cladding. It is urgent to investigate the effect of machining on the corrosion resistance of the laser cladded layers, so as to avoid the reduction of corrosion resistance due to the use of inappropriate cutting parameters. In the present study, the influence of turning-induced surface roughness on the corrosion resistance from the viewpoint of corrosion potential was analyzed first. The corrosion potential is the result of the effect of roughness height parameters and functional parameters. Second, the effect of the machining and subsequent burnishing on the corrosion resistance was analyzed by comparing the corrosion behaviors of the turned and burnished surfaces. The polarization resistance is critically increased by subsequent burnishing. Third, the sensitivity of the machined surface on corrosion resistance was analyzed by EIS method. The strengthening mechanism of machining and subsequent burnishing on the corrosion resistance was determined. On the basis of this research, it is expected to be used to guide the selection of appropriate feed parameter in prior turning to improve the strengthening effect of subsequent burnishing, and then, to improve the surface integrity and corrosion resistance of the laser cladded layer.