Automobile Leaf Spring: An Overview.

In the present scenario, human safety is one of the most important parameters in design and manufacturing of a vehicle, which is the reason every organization is very keen in ensuring durability and reliability of automobile components. One such critical component in the vehicle is the suspension system consisting of leaf springs whose primary role is to absorb and store strain energy, which can be further released slowly during operation. This plays a vital role in ensuring both human safety and ride comfort. Also, it acts as a structural member to establish linkage between chassis frame and axle. In this paper, we would like to review the previous work done by researchers in the field of leaf spring design, FEM analysis, manufacturing process optimisation, durability testing and failure analysis, alternate material selection (both steel and composite) for weight and cost optimization. Detailed failure mode investigation on modes of failure and its causative factors like improper heat treatment, surface decarburization, hydrogen embrittlement, fretting fatigue and corrosion pitting is discussed. This review provides the improvement scope in current design and manufacturing processes, which will enhance the durability and avoid premature failure of leaf springs. The paper discusses about the additional life enhancement manufacturing processes such as shot peening, ausforming during heat treatment, lubrication improvement and corrosion prevention by using solid lubricants. These processes are proposed to be considered at design stage itself to optimise the size and weight of suspension by reducing number of leaves for the same vehicle application. [ABSTRACT FROM AUTHOR]