Industrial Engineering

Biography

Biography: Joseph Stokes

Abstract

To date economic and rapid solutions to equipment failure caused by wear and corrosion in many industries but partivcularly in oil and gas industries have been reduced through the deposition of cermets using HVOF thermal spray coatings especially tungsten carbide cobalt (Diamalloy 2004) deposits to reduce wear effects and Inconel 625 (Diamalloy 1005) to prevent corrosion . Research generally focused on monolitic coatings (single layers) or multi-layers where one material was applied upon another. However the trend is now moving towards the development of bimodal powders to form a composite coating structure and from here to the mixing of nano and micro size feedstock powders, through the addition of nano-structured WC-Co. This research paper demonstrates the benefit of using blended nano structured WC-Co with Inconel 625 over layered type coatings when subjected to hostile mechanical/wear/corrosion environments. This was achieved through design of experiment (DOE) analysis to study the influence of different powder percentage on the coating performance such as coating microstructure and coating mechanical performance, such as; three-point bending tests and hardness measurement. The results showed that 75% weight of nanostructured WC-12Co mixed with Diamalloy 1005 Inconel-625 was superior comparec to any other percentage mixture of the two powders and compared to single layer deposoition of each coating, due to the strong adhesion of WC nano size grains at the substrate/coating interface through improved mechanical interlocking and reduce the possibility of cracks initiation. The results show promise in terms the current maintenance challenges experience by the Oil/Gas industry today; in terms of possibly extending the life of components, plus providing huge economic savings.