Thermal Fatigue Analysis of Sliding Composite Leaf Spring Based on Bench Test.

Leaf spring is often used in commercial vehicles' suspension systems to ensure ride comfort and support dynamic wheel loads. This paper studies the thermal failure mechanism of sliding composite leaf springs. The thermal failure temperature and thermal failure mode were investigated by the bench test. The results show that when the temperature exceeds the glass transition temperature (Tg point 115 °C) for 30mins, cracks will appear around the bolt hole of the composite body. The damaged area expanded with the continuous increase in temperature. When the gap (between the fiber and the resin) grows to a stable stage, the failure temperature of the composite body becomes stable. The crack propagates first longitudinally first and then transverse. When the transverse crack is transformed into a sharp fracture, the spring may fail with decreased stiffness. This study can better understand the performance of composite leaf springs working at high temperatures and provide an effective reference for the study of the spring's service condition. [ABSTRACT FROM AUTHOR]