Development of novel 'Duplex NiCr-coated' nanostructured HVOF WC-17Ni(80/20)Cr coatings for severe wear applications

摘要

Thermally sprayed coatings have long been used to develop engineered surfaces for protection from severe degradation due to abrasive/erosive wear. High Velocity Oxy-Fuel (HVOF) thermal sprayed cermet composite coatings based on WC-Co systems offer better wear resistance and greater application flexibility compared with the traditional surface treatment techniques such as hardfacing. Recently, the development of nanostructured surfaces based on HVOF deposition of nano-grain WC reinforced in a variety of alloy matrix based cermet systems have gained research focus thanks to their initial performance results, including high hardness and wear properties without concomitant loss of ductility or fracture toughness in the sprayed coatings. In this research, the novel design and manufacturing of the 'duplex Co-coated' nanostructured WC-17Ni(80/20)Cr cermet powder is developed. The spraying of the feedstock is carried out using a diamond jet DJ2600 HVOF spray gun. In this study the mechanical properties of the novel coating are investigated and compared with the industry-standard microstructured WC-10Ni-5Cr coating.