Microstructure and anti-corrosion performance of laser cladded Nb-modified Ni-based alloy coatings

Abstract

In this work, Ni-based alloy coatings incorporated with Nb mass fractions of 0%, 3%, 6%, and 9% were successfully fabricated by laser cladding. The morphology, chemical composition, and phases of the obtained Nb-modified Ni-based coatings were characterized, and the effects of Nb contents on their electrochemical performance and immersion rates in 3.5 wt% NaCl solution were analyzed. The results show that the Ni-based coating with low Nb exhibits the most compact and refined microstructure, the best electrochemical passivation, and the lowest immersion corrosion rate of 3.30 × 10−3 mm/year. However, with increasing Nb content, the Laves phase is accumulated, and dendritic growth is promoted, which significantly decreases the coating passive stability and worsens the anti-corrosion performance.

The use of a superhard boron nitride composite c-BN+h-BN with increased resistance to brittle cracking for anti-wear coatings

“…The analysis of the literature shows that coatings made of composite materials are more often used due to the fact that they often have better properties (antiabrasion, 11,12 tribological, 13,14 anticorrosion, 15,16 etc.) than coatings made of simple materials (made of one element or one single-phase two-component compound-e.g.…”