Optimization Design And Finite Element Analysis Of The Composite Leaf Spring For The Automobile

The traditional automobile leaf spring is always made up of spring steel with well-resistant fatigue.But with the improvement of the automobile safety,saving energy and environment protection,light weight of the automobile gradually becomes a focus of the study. As an important light weight material,resin composite replaces the traditional metal material to an increasing extent.Compared with the traditional material such as steel and aluminum alloy.resin composite has the advantage of light weight, high strength,corrosion-resistant,good vibration damping,good designability and easy processing.And practice has proved that resin composite largely used in automobile can not only lighten the weight obviously,reduce oil consumption and improve comfort,but also reduce pollution and lower manufacturing cost.Therefore,studying the technology of the automobile composite leaf spring at home and abroad and designing it suitable for the development of the automobile industry in China have great significance to the light weight of the leaf spring,the improvement of the driving comfort,stability and its endurance,short design cycle and high efficiency.This article aims to research automobile leaf spring. According to the composite characteristic of the light weight and high strength,suitable composite material,namely E glass fiber reinforced resin matrix composite,is selected to replace spring steel.And the leaf spring is optimized to in order to finally reach the purpose of lightweight.First, an overview of developments in the area of the suspension system,leaf spring and composite material is summarized.Then the composite laminated board theory is introduced,containing its characteristic,strain,inner force as well as the relationship of stress and strain.According to the composite laminated board theory,the optimized mathematical module of composite leaf spring has been established,setting the minimum mess as target,the size parameter of the leaf spring as design variable,and the intensity and rigidity as restriction.After leaf spring is optimized by using MATLAB software,its3-D module is established using PROE software and then imported into ANSYS software to analyze the assembly process of the leaf spring,the strain,the stress and the stiffness.Finally,the leaf spring’s displacement response and dynamic stiffness are studied under sinusoidal load, proceeding as well the simulation analysis and the prediction of the fatigue life.