Design Development & Analysis of Composite Mono Leaf Spring

Leaf spring is important element of suspension system. Ride comfort and load carrying capacity of vehicle mainly depend upon the leaf spring. It has to withstand numerous load cycles without fatigue failure so it is needed to assess the fatigue life of leaf spring.

In the present scenario, weight reduction has been the main focus of the automobile manufacturers. The suspension leaf spring is one of the most potential items for weight reduction in automobiles as it contributes to 10–20% of the unsprung mass. The introduction of composite materials made it possible to reduce the weight of the leaf spring without any reduction in load carrying capacity and stiffness. Stress, stiffness and fatigue life are the performance measures of the leaf spring.

In the present work, static and fatigue analysis of composite mono leaf spring made up of E-glass/epoxy material. The dimensions of an existing conventional steel leaf spring of a light commercial vehicle are taken and are verified by design calculations. Static Stress, stiffness results obtained by analytical method (SAE Manual), numerical results (FEA) with experimental results. Also Fatigue analysis is carried out to assess the fatigue using numerical software ANSYS V14.5 and results are validated using experimental fatigue test. Weight reduction up to 66% is achieved for an E-glass composite in comparison with steel leaf spring fatigue life has been increased up to 66 Lac cycles.