基于多轴载荷的汽车控制臂疲劳载荷块编制

Block Cycle Load Compilation for Automobile Control Arm Fatigue Test Based on Multiaxial Load

目前大多数控制臂台架疲劳载荷为单向加载的块谱,忽略了载荷的多轴性。依据已测得的控制臂试验场道路载荷谱,通过多轴雨流投影方法分析了其载荷的多轴性,并以多轴雨流投影结果一致为目标,通过迭代方法求解获得其考虑载荷多轴性的载荷块谱。再通过疲劳计算方法对比了单轴与多轴载荷块在寿命预测的差异性,并与控制臂应变采集测试点的疲劳损伤对比,发现考虑多轴的载荷块具有更高的预测精度。载荷多轴性的载荷块编制方法可为汽车其他零件台架疲劳载荷块编制提供参考。

At present,most of the fatigue loads of the control arm are uniaxial load.Based on the test road load spectrum of the control arm,the multiaxial load characteristics was analyzed by the method of multiaxial rain-flow projection.In order to obtain consistent results of multiaxial rain-flow projection,the block cycle load with the same multiaxial characteristics was obtained by iterative solution method.Then the uniaxial and multiaxial block cycle load for fatigue bench test were compiled by fatigue calculation.Compared with the fatigue damage at the test point,it is found that the multiaxial block cycle load with consideration of multi-axes has higher prediction accuracy.The compilation method of block cycle load considering the multi-axes can provide reference for the fatigue block-spectrum of other automobile parts.