Assessing the environmental impacts of thermally sprayed WC-Co coatings deposited from zinc-process recycled feedstock

Cemented carbides, particularly tungsten carbide cobalt (WC-Co), represent a growing material flow with established recycling techniques, offering a viable alternative to primary raw materials in components and applications based on cemented carbides. However, the use of recycled feedstock in thermal sprayed coatings and its associated environmental impacts are less addressed in the field. This study aims to investigate the environmental impacts and potential benefits of applying zinc-process recycled powder materials in thermal spray processes compared to traditional primary raw materials. A life cycle assessment (LCA) was conducted for thermal spray coating methods, HVOF and HVAF operated with diverse fuels, employing recycled WC-Co as a material feedstock. The benefit of applying recycled feedstock is illustrated by comparing the environmental performance indicators, such as CO2 footprint and cumulative energy demand (CED), of recycled raw material against primary raw materials in the thermal spray process.