球墨铸铁转向节柱疲劳性能研究

Research on Fatigue Performance of Ductile Iron Steering Knuckle

针对某车型球墨铸铁转向节柱转向横拉杆臂疲劳台架试验不合格的情况,利用CAE技术模拟分析了该零件结构对疲劳性能的影响,通过对比试验研究了球墨铸铁主要化学成分对球墨铸铁机械性能和疲劳寿命的影响,并提出局部增大壁厚、改善过渡圆角的改进措施。经过试验验证,在质量不增加的情况下,改进后的球墨铸铁转向节柱疲劳寿命比改进前提高30%。

Because tie rod arm of the ductile iron steering knuckle failed in the bench fatigue test, influence of this component structure on fatigue performance is simulated with CAE technology, then the influence of main chemical compositions of ductile iron on mechanical performance and fatigue life of ductile iron is investigated with comparative test, then a modification of thickening local wall thickness and improving transitional fillet is presented. The test verifies that fatigue life of the modified ductile iron steering knuckle is improved by 30% without adding mass.