轿车后轴疲劳耐久性及振动模态参数扫频  

Fatigue Durability and Vibration Modal Parameter Frequency Sweep for Car Rear Axle

作　　者：门玉琢[1] 于海波 霍娜 

机构地区：[1]长春工程学院机电工程学院,长春130012 [2]中国第一汽车股份有限公司技术中心,长春130011

出　　处：《机械设计与制造》2012年第9期198-200,共3页Machinery Design & Manufacture

基　　金：国家自然科学基金(51008034);吉林省科技发展计划资助项目(201201135)

摘　　要：针对某型号轿车试验场强化路可靠性试验阶段出现的后轴断裂问题,对该车后轴断裂部位及有限元分析的薄弱位置进行了应变载荷谱测量,重点对比计算耐久强化路的后轴断裂裂纹处的疲劳损伤;同时利用MTS六通道耦合系统对该试验样车和对标车辆的后轴和车身进行振动模态扫频,通过振动扫频分析两车后轴振动频率差异原因以及和车身振动频率的关系。强化试验和扫频结果表明,两车后轴的疲劳损伤主要集中在试验场搓板路面,车速对试验样车的疲劳损伤影响波动显著,搓板路强迫振动激励大于20Hz时两车损伤差别较大,后轴的振动模态频率与搓板路激励频率较接近,造成试验样车后轴具有较高的应力分布而产生疲劳断裂,研究结果对断裂后轴的结构改进及提高后轴的疲劳强度提供了重要依据。In order to research the fatigue fracture problem of the rear axle of a domestic car at the reliability test stage on the durable enhancement roads of proving ground, the strain loading spectrum ofthe rear axle fracture location and the weak points of the finite element analysis was measured.The fatigue damage of the broken crack at the rear axle of the durable enhancement roads was calculated and contrasted detailedly.At the same time ,a six-channel MTS coupling system was used to conduct the vibration mode frequency sweep to the rear axle and body of test car and the benchmarking car,and through vibration frequency sweep,an analysis of the reason of differences between the two cars and its relationship with the body vibration frequency was made.The enhancement test and frequency sweep results show that the fatigue damage of two vehicles focuses mainly on the washboard road,and the impact of the speed on the fatigue car fluctuates significantly, and also the damages of the two cars vary greatly when the forced vibration excitation frequency of the washboard road is greater than 20Hz and the vibration modal frequency of the rear axle is close to the excitation frequency of the washboard road,causing high stress distribution and then fatigue fracture to the rear axle of the test car.The test results have provided an im- portant basis for the structural improvement of the broken rear axle and the enhancement in the fatigue strength of the rear axle.

关 键 词：疲劳损伤 试验场 后轴 振动扫频 

分 类 号：TH16[机械工程—机械制造及自动化] U461.7[机械工程—车辆工程]