Effect of laser spot overlap on the mechanical properties and corrosion resistance of laser-assisted electrodeposited Ni-based coatings

Abstract

In this study, a laser-assisted electrodeposition method is used to prepare Ni–Co–W and amorphous Ni–P coatings for different laser scanning rates. The laser scanning rate is an important parameter as it can be used to adjust the laser spot overlap (ε) and energy distribution of the laser pulse, thereby affecting the properties and performance of the coatings. The effect of ε on the various properties of the Ni–Co–W and Ni–P coatings is explored. The experimental results show that a change in ε influences the surface morphology, mechanical properties, and corrosion resistance of the coatings. For ε = 85%, the Ni–Co–W and Ni–P coatings exhibit the best surface morphology. The Ni content of both the Ni–Co–W and Ni–P coatings is found to decrease with an increasing ε, whereas the Co and P contents are found to increase with ε. However, the residual tensile stress of the Ni–P coating fails to improve with an increasing ε. The wear and corrosion resistances of the Ni–Co–W coating increase with ε. Moreover, a change in ε affects the intensities of the (111) and (220) diffraction peaks of Ni–Co–W. For ε = 85%, both the Ni–Co–W and Ni–P coatings exhibit good wear and corrosion resistances.