Research On Lightweight Of Automobile Steering Knuckle

The steering knuckle is an important part of the automobile chassis.In the Mc Pherson suspension,the upper end of the steering knuckle is matched with the automobile shock absorber,and the lower end is matched with the lower swing arm;In the double wishbone suspension,the upper end of the steering knuckle is matched with the upper swing arm,and the lower end is matched with the lower swing arm.At the same time,the steering knuckle also needs to cooperate with the steering arm to play the steering function;Cooperate with brake caliper to brake;Cooperate with the bearing to connect the tire with the suspension system to make the vehicle run stably.In the process of vehicle driving,because of the complex road conditions,the load on the steering knuckle is also complex and changeable,so in order to meet the requirements of complex working conditions,the steering knuckle needs to have enough stiffness and strength.However,the larger unsprung mass will not only seriously affect the vehicle’s handling and comfort,but also make the vehicle’s fuel consumption higher;For electric vehicles,larger weight will lead to reduced range.In order to improve the fuel economy and vehicle handling,and improve the vehicle endurance,it is necessary to design the steering knuckle lightweight.In this paper,an electric vehicle is taken as the background,and aluminum alloy material is used to realize the lightweight design of steering knuckle product through topology optimization and parameter optimization:The suspension of this electric vehicle is of Mc Pherson type structure and adopts cast iron steering knuckle.According to the most common driving environment in China and the driving habits of ordinary drivers,this paper carefully analyzes and selects five representative working conditions during the driving process of the vehicle.Combined with the knowledge of vehicle system dynamics,this paper analyzes the forces on the steering knuckle under these five working conditions,The loads under different working conditions are obtained.According to the calculated load,ABAQUS is used to analyze the stress distribution of the cast iron steering knuckle and the stress displacement of each installation point under various working conditions,and the stiffness and strength of the steering knuckle are obtained.According to the analysis results,the steering knuckle can reach the predetermined performance index under various working conditions.The fatigue test of the cast iron steering knuckle is carried out,and it is verified that the steering knuckle can meet the predetermined life requirements.The model of cast aluminum steering knuckle is drawn according to the original results of the rigid point and finite element analysis of the cast iron knuckle.The multi-objective optimization method is used to optimize the reconstructed model of cast aluminum steering knuckle under five typical conditions.According to the results of the topology optimization,the model of cast aluminum steering knuckle is modified by engineering.Then,the mesh deformation technology is used to model the steering knuckle parameterization,and five typical optimization dimensions are selected.In order to improve the efficiency of optimization,the second-order response surface of steering knuckle optimization is established.The optimization method of NSGA-II is used to optimize the parameters of the model,and the optimized parameters are obtained.The results show that the strength of the knuckle meets the requirements of various working conditions.Compared with the cast iron knuckle,the stiffness of each installation position has been improved,and the weight of the knuckle is reduced by46.5%.Finally,the full text is summarized,and the future of automotive lightweight is further prospected!...