Design and analysis of composite mono leaf spring for passenger cars

Abstract

The suspension leaf spring is one of the most crucial parts which help in improving the ride quality of an automobile. It is devised to absorb, store and release the energy. A considerable reduction of unsprung weight is generally adopted to improve comfort and ride quality. A simple but yet effective method to meet this objective is replacing the metallic leaf spring by a composite spring. Other than weight reduction, the composite leaf spring provides additional benefits such as high strength to weight ratio and high elastic strain energy storage capacity. In this research work, a steel mono leaf spring which could be employed in passenger cars is taken as reference, which is further analyzed and compared with composite mono leaf design. The objective of this research work is to investigate the suitability of hybrid composite spring which incorporates carbon fibers and flax fibers as primary and secondary reinforcements respectively. The natural frequency of the composite leaf spring was found to be 93% more than that of steel. Moreover, the incorporation of flax layers in between carbon fibers increased the factor of safety and strain energy owing to its high damping properties.