A speed pedelec can have up to a 4,000W engine that operates without pedal assistance, and the parts of the engine need to be made from materials with a high Comparative Tracking Index (CTI) to prevent electrical tracking that could cause burning, smouldering or even fire. DSM’s material solutions for such applications provide unmatched CTI ratings that reduce the risk of high voltage connector failures, even with short creepage distances.
Xytron polyphenylene sulphide (PPS) is an inherently chemical-resistant, flame-retardant material with high stiffness up to a glass transition temperature of 90°C with a continuous use temperature (CUT) of 240-260°C and a melting point of 280°C. Arnite polyethylene terephthalate (PET) and polybutylene terephthalate (PBT) materials offer high strength, rigidity and dimension stability for manufacturing thin-walled parts.
Also, engine parts manufacturers are switching from polyoxymethylene gears to plastic gears made of a material solution that can handle an increased mechanical load caused by an increase in power and torque, plus reduce weight, increase speed of production cycles and bring more improvements to NVH performance.
DSM’s Stanyl polyamide 46 (PA46) is a material solution designed for replacing components in various demanding wear and friction applications, found in e-bikes, and offers high wear resistance and low friction, as well as high fatigue strength that gear components require. Due to its very high crystallinity, the material retains its mechanical properties at temperatures up to 220°C making it ideal for high-performance applications, where it outperforms polyphthalamide’s (PPA’s such as PA6T and PA9T), PPS, PA66 and POM.