Effect of Pulse and Direct Current Electrodeposition on Microstructure, Surface, and Scratch Resistance Properties of Ni–W Alloy and Ni–W–SiC Composite Coatings

Sami Bin Humam¹，Gobinda Gyawali²，Dhani Ram Dhakal¹，Jin-Hyuk Choi¹，Soo Wohn Lee¹

1. Department of Environmental and Bio-Chemical Engineering,Sun Moon University2. Department of Fusion Science and Technology,Sun Moon University

摘 要：The present work aims to study the influence of direct current and pulse current techniques as well as embedded SiC nanoparticles on the mechanical properties of the electrodeposited Ni–W coating. The electrodeposited coatings were studied for morphological, microstructural, mechanical, and scratch resistance properties using the surface roughness tester, scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, Vickers microhardness, and scratch tester. Application of pulse current exhibited relatively homogeneous and smooth surface of the coatings. A remarkable increment of microhardness was observed in both Ni–W and Ni–W–SiC coatings prepared under pulse current as compared to the direct current technique. Similarly, the scratch test revealed a considerable improvement in the scratch resistance behavior of the Ni–W alloy and the composite coatings from the pulsed current condition. Hence, the application of pulse current not only improved the surface-and microstructure-related properties but also enhanced the Vickers microhardness and scratch resistance properties of the coatings. In addition, the reduction in micro-cracks revealed the improvement in scratch resistance properties of the coatings due to the incorporated SiC nanoparticles into the Ni–W alloy matrix.

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