Basalt fibers as a sustainable alternative to glass fibers in the reinforcement of polyamide 6 for gear applications

With the increasing use of e-mobility, the demand for high-quality materials to produce polymer gears is growing.Due to the tendency towards using natural materials and reducing carbon footprint, basalt fibers (BF) are tested as a substitute for glass fibers (GF).For this purpose, composites of polyamide 6 (PA6) with GF and BF, with and without compatibilizer and polytetrafluoroethylene (PTFE) are produced, tested, and properties compared.The mechanical, thermomechanical, thermal, and tribological properties of the composites, as well as the size of the fibers after the production of the composites and after injection molding, are determined.The compatibilizer improves the impact strength, while the glass fibers have a better reinforcing effect.The fibers increase crystallinity, but the effect is minimal.The thermal conductivity increases approximately the same for both fibers and is highest at composites that, in addition to 30% fibers, also contain PTFE.The tribological properties are comparable but slightly better for glass fibers.The fiber length is greatly reduced during the production of the composites and is around 200-300 m in both cases.SEM imaging and mapping analysis show good dispersion of the fibers in the polymer and relatively poor compatibility with PA6.