Performance Analysis And Lightweight Design For Side Impact Safety Part Of Body-in-white

Safety,energy saving,and environmental protection is the development trend of automobile industry,lightweight car one of the main measures of energy saving and emission reduction.Lightweight of automotive is divided into the body structure optimization design and application of new material,new craft three important technical paths.Lightweight car body is mainly subject to the limit of the performance of vehicle passive safety and harshness(NVH),and lightweight car body must under the condition of guaranteed performance has practical application value.In the process of car crash,safety parts of vehicle are under impact load,deformation and energy absorption.On the one hand,safety parts of vehicle is important to ensure the stiffness of car body and basic performance of harshness(NVH)On the other hand,they are the sensitive parts of body structure lightweight at the same time.Visibly,the security lightweight design is a key problem for body structure lightweight technology.Therefore,the analysis of body structure safety performance and lightweight design has important theoretical significance and engineering application value.In this paper,with an independent brand of car body as the research object,its side touch safety parts,B-pillar is performance is analyzed and lightweight design is undertook.Under the condition of ensuring the vehicle side collision performance requirements,achieve the purpose of weight loss,and the analysis and evaluation on the effect of lightweight.The main work of this paper is as follows:Firstly,a finite element analysis model of body structure is established.Then,according to the requirements of national standard GB20071-2006 "occupant protection of automobile side impact",the finite element analysis model of vehicle side impact is established by integrating the vehicle model with the chassis and powertrain.Next,the simulation results of the side impact performance of the vehicle are verified by simulation and experimental results.The validity of the finite element model of the vehicle side impact is verified.Secondly,the finite element model of B-pillar inner plate with different thickness and unequal strength laser welding is established by combining B-pillar ideal deformation mode and Tailor-Welded Blank technology(TWB).The impact resistance of the B-pillar is analyzed,and the Optimal Latin Hypercube Design method(OLHD)is used to obtain the sample points.According to the test sample point,the radial basis function model is established.After checking the accuracy of the agent model,the optimal solution set is obtained by the non-inferior ranking genetic algorithm for the multi-objective and lightweight optimization of the B-pillar inner plate.The results show that the mass loss of the inner panel of the car B is 15.8%,the maximum penetration of the chest is reduced by 44.0% and the intrusion rate is reduced by 11.4%.In the realization of the simulation,B-pillar light weight while improving the safety of the side of the body.Finally,the performance analysis and comparison of B-pillars before and after B-pillar optimization are carried out.By comparing the deformation of B-pillars with the lateral side of the vehicle,the B-pillars correspond to the head,beltline,rib,abdomen,H point,The results show that the optimized B-pillar structure approaches the ideal deformation mode.The maximum invasiveness and intrusion rate meet the specified requirements,and the collision performance is greatly improved.