Erosion behaviour of laser cladded Inconel 625 — Vanadium carbide metal matrix composites coatings manufactured with different reinforcement contents

Abstract

Erosive wear is a primary factor contributing to the potential failure of oil and gas components. Laser cladding of hard coatings constitutes one of the possible solutions to extend the components' service life. Among the viable options, the use of vanadium carbide reinforcement could provide a series of advantages. Vanadium carbide possess in fact similar hardness but significant lower density than other more conventional metal matrix composite's reinforcements. However, there has been limited work done in characterising the wear behaviour of such solutions in order to prove their viability. In this paper, the erosion behaviour of Inconel 625 – vanadium carbide metal matrix composite coatings deposited by laser cladding was investigated. Three different contents of reinforcement, 10, 20, and 30 wt%, were studied. Optical confocal microscopy was used to measure the coatings' volume loss after the tests performed with an air jet erosion tester following the ASTM G76 recommendations. The results were correlated with microstructural observations and hardness measurements. The generation of secondary carbides were detected in the coatings fabricated with 20 and 30 wt% reinforcement. In addition, a linear increase of the matrix hardness was observed while increasing the content of reinforcement in the coatings. On the other hand, the brittle behaviour of the primary vanadium carbide particles incorporated in the coatings becomes predominant for contents of 30 wt% reinforcement and reduces the coatings erosion resistance.