不同工况下车用复合材料板簧的动态疲劳测试研究

Research on Dynamic Fatigue Test of Vehicle Composite Leaf Spring Under Different Working Conditions

为了加快复合材料板簧在汽车轻量化进程中的推广应用,各向异性复合材料板簧的性能测试尤为重要,而动态疲劳性能直接反映了复合材料板簧在实际使用过程中的可靠性。当前对复合材料板簧的疲劳性能测试基本停留在垂向疲劳,对实际使用过程经常出现的制动、转弯动态疲劳的测试研究鲜有报道。本工作针对复合材料板簧在不同工况下的受力情况,设计了垂向、制动、转弯疲劳测试方法,并利用有限元分析方法对刚度、最大承载力、制动工况、转向工况及不同动态疲劳进行了研究。同时,通过复合材料板簧静载刚度、最大承载力和垂向动态疲劳的台架试验,验证了有限元分析模型的可靠性。最后,限定疲劳寿命及复合材料板簧许用应力值,计算得到板簧垂向疲劳极限载荷为垂向1.5倍满载荷;制动疲劳极限载荷为垂向1.5倍满载荷,长度方向1.5倍满载荷;转弯疲劳极限载荷为垂向满载荷,侧向0.8倍载荷。

In order to speed up the application of composite leaf spring in automobile lightweight process, the performance test of anisotropic composite leaf spring is particularly important, and the dynamic fatigue performance directly reflects the reliability of composite leaf spring in practical use. At present, the fatigue performance test of composite leaf spring basically stays in the vertical fatigue, and there are few reports on the test research of braking and steering dynamic fatigue that often occurs in the actual use process. In this work, the vertical, braking and turning fatigue test methods are designed for the composite leaf spring under different working conditions. The stiffness, maximum bearing capacity, braking condition, steering condition and different dynamic fatigue are studied by finite element analysis method. At the same time, the reliability of the finite element analysis model is verified by the static load stiffness, maximum bearing capacity and vertical dynamic fatigue test of the composite leaf spring. Finally, limiting the fatigue life and the allowable stress value of the composite leaf spring, the vertical fatigue limit load of the leaf spring is1.5 times of the vertical full load. The braking fatigue limit load is 1.5 times full load in vertical direction and 1.5 times full load in length direction.Steering fatigue limit load is full load in vertical direction and 0.8 times full load in lateral direction.