Societal flows of cemented tungsten carbide – the case of tire studs

Other conference contribution, 2018

Cemented tungsten carbide (WC-Co) is applied in many different applications due to its properties of high hardness and toughness. Tire studs represent one such application and is used in many countries in order to increase the friction between the tires and the winter road. Previous studies have indicated emissions of WC-Co nanoparticles originating from tire stud use but the magnitude of these emissions remain unknown. This study conducted a material flow analysis for tungsten, which is the main constituent of the tire stud pins, and quantified WC-Co nanoparticle emissions from the use of tire studs in Sweden. The results show that 100% of the tungsten in tire studs become dissipated and that 0% is functionally recycled. A comparison of WC-Co nanoparticle emissions with emissions of some engineered nanomaterials in various applications in Sweden showed that the WC-Co nanoparticle emissions were larger than for e.g. nanosilver.