Optimize Analysis And Research Of The Lower Control Arm Of A Certain Suv Rear Suspension

It is an important part of automobile called the suspension system that determine the driving performance and safety, and directly affect the normal use of the car. It is an important index to measure performance and affect the sales. In order to reduce the costs and the period of research and development, the major car manufacturers introducing new suspension system which is more and more platform, generalization and modularization.Based on the fracture problem of automotive suspension as the research subject, this dissertation choose a fracture case of the lower control arm(LCA) of the sport-utility vehicle as the research object. Combining with the LCA fracture, the failure analysis and finite element analysis method was adopted, the exploration and study of the causes of suspension fracture and optimizing corrective actions.In this paper,the main research contents are as follows:(1) According to fracture sample information of a SUV LCA, using the method of failure analysis, chemical composition of the samples, hardness, metallographic analysis, fracture analysis, mechanical properties were tested. In this paper, we analyzes the specific failure forms of the LCA,summed up the specific failure reasons of the product and the corresponding failure mechanism, and puts forward corresponding preventive measures.(2) Established the dynamic model of a sport-utility vehicle’s rear suspension, and calculated the loads of the LCA by the Adams Car module for dynamic analysis.(3) Established the geometry model and the finite model, and calculated the strength by Nastran software. First, design the geometry model by the catia; Second, handle the finite model, including the clearing to geometric model,meshing, boundary conditions and load handling etc.; Then, solve the finite element by Nasran and read the results of analysis by Hyperview software. Finally, according to the results of the analysis to take the maximum stress area of the fractured LCA in a variety of ultimate load condition.(4) Established the fatigue model, and calculated the damage by n Code 9.0 software.(5) According to the result of the failure analysis and finite element analysis, we found out the failure of the LCA, and proposed the improvement program and the structure optimization; Finally, this optimized scheme was verified through the finite element analysis, and the results meet the design requirements.To sum up, through the research of this topic, the method of analysis about the suspension fracture are explored, This method provides the beneficial reference for engineering and technical personnel engaged in research and development of the automobile suspension.