基于路谱载荷的副车架加速耐久台架试验的开发与应用

以试验场路试中某车型前副车架控制臂安装点处焊缝开裂失效为研究对象,对控制臂的路谱载荷进行了采集。将控制臂安装点处的路谱载荷,运用雨流计数法,并根据虚拟的S-N曲线和Miner线性疲劳损伤累积理论,得到路谱载荷下控制臂安装点的伪损伤。根据损伤等效原理,反推出在一定循环次数下,与路谱载荷损伤等效的等幅载荷的幅值。利用等幅载荷对副车架进行加速耐久台架试验验证,发现失效模式、失效寿命与试验场整车试验取得了较好的相关性。通过加速耐久台架试验,快速验证了改进方案,并通过了后续的试验场路试验证。

Development and Application of Accelerated Durability Bench Test for Sub-frame Based on RLD

The welding seam crack failure of the control arm mounting point on front sub-frame in the durability test of proving ground was taken as a research object,road load data acquisition activity on control arms was performed.Based on rain-flow counting method,pseudo S-N curve and Miner liner fatigue damage accumulation theory,the pseudo damage of the control arm mounting point on proving ground was achieved.According to damage equivalence theory,the amplitude of a constant amplitude load equivalent to the road load data damage under a certain number of cycles were derived reversely.Accelerated durability bench test is performed to verify the durability attribute of front sub-frame based on the constant amplitude load,there is good correlation result between bench test and proving ground test on the failure mode and failure life.After the accelerated durability bench test,the improved proposal is quickly verified,passes the accelerated durability bench test and complete vehicle durability test in proving ground.