扭力梁式后悬架扭转工况下横梁疲劳特性研究  

Study on fatigue characteristics of crossbeam in torsion-beam rear suspension under torsional condition

作　　者：王韬 杨旭静[1] 李茂君 秦银平 左捍亭 齐军 WANG Tao;YANG Xu-jing;LI Mao-jun;QIN Yin-ping;ZUO Han-ting;QI Jun(State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body,Hunan University,Changsha 410082,China;Shanghai Huizhong Automobile Manufacturing Co.,Ltd.,Shanghai 201814,China)

机构地区：[1]湖南大学机械与运载工程学院,湖南长沙410082 [2]上海汇众汽车制造有限公司,上海201814

出　　处：《塑性工程学报》2024年第1期231-239,共9页Journal of Plasticity Engineering

基　　金：国家自然科学基金资助项目(51875188)。

摘　　要：基于有限元仿真,对扭力梁式后悬架扭转工况下横梁的疲劳特性进行了分析,提出了一种利用等效试样预测复杂结构零件疲劳寿命的新方法;建立了扭力梁式后悬架仿真模型,分析了横梁的应力分布规律;基于静力学分析结果,结合FB590高强钢疲劳寿命曲线、成形后横梁表面粗糙度以及表面残余应力,根据名义应力法和Gerber平均应力修正计算了横梁的疲劳寿命,并根据危险区弯曲变形程度设计了不同弯曲半径的等效试样(AR、R20和R10)进行疲劳试验和疲劳断口分析,实现了对横梁疲劳台架试验结果的有效预测。结果表明,在扭转工况下横梁疲劳危险区与应力集中区位于过渡段转角处,横梁的工况幅值-寿命曲线有效覆盖了服役情况下的所有负载情况,并得到了实际载荷谱的应力幅值参考范围;在台架试验中,R10与AR、R20等效试样交点寿命在横梁实际断裂寿命区域内,表明设计的等效试样疲劳试验可以有效表征横梁危险区的疲劳性能。The fatigue characteristic of crossbeam in torsion-beam rear suspension under torsional condition was analyzed based on finite element simulation,and a new method for predicting the fatigue life of complex structural parts by equivalent specimens was proposed.The simulation model of torsion-beam rear suspension was established,and the stress distribution laws of crossbeam were analyzed.Based on static analysis results,combined with the fatigue life curves of FB590 high-strength steel,the surface roughness and surface residual stress of the formed crossbeam,the fatigue life of crossbeam was calculated according to the nominal stress method and the Gerber average stress correction.According to the bending deformation degree in the danger area,the equivalent specimens(AR,R20 and R10)with different bending radius were designed for fatigue tests and fatigue fracture analysis,which realize the effective prediction of the test results of cross-beam fatigue bench.The results show that the fatigue danger area and stress concentration area of crossbeam are located at the corner of the transition section under torsion condition.The amplitude-life curves of crossbeam effectively cover all load conditions under service conditions,and the reference range of stress amplitude of actual load spectrum is obtained.The intersection life between equivalent specimens R10 and AR,R10 and R20 is within the actual fracture life area of crossbeam in the bench test,which indicates that the designed fatigue test of equivalent specimen can effectively characterize the fatigue performance of crossbeam in the dangerous area.

关 键 词：扭力梁式后悬架 等效试样 疲劳特性 疲劳寿命预测 

分 类 号：O346.2[理学—固体力学]