ABSTRACT
Timing belts are very typical rubber-cord composites, and fibers (Miller, 1991) such as glass fiber, carbon fiber, polyamide fiber are often used as a reinforcement. Modern automotive timing belts last the life of the vehicle and run in oil. Care must be taken when reading historical literature that related to lower performing timing belts. Iizuka et al identified in 1994 two types of failure mode (Iizuka et al., 1994). One was the crack growth at both sides of the tooth roots, which led to the failure of the tooth. The other was the stranded fiber filaments separation under tension, causing the failure of the cord, which was for the time considered to be the main failure mode under normal driving conditions. When timing belts last the lifetime of the car engine, there is a need for accelerated, amplified laboratory testing.
