基于低载强化的悬架弹簧耐久性评价

DURABILITY EVALUATION OF SUSPENSION SPRING BASED ON THE LOW AMPLITUDE LOAD STRENGTHENING

以某轿车后悬架弹簧为对象,研究室内快速耐久性试验与耐久性里程之间的关系,对悬架弹簧的耐久性进行评价。将低载强化理论引入某试车场强化的比利时路面载荷谱组合谱的损伤分析过程中,处于低载强化区间内的载荷提高了零件疲劳强度,根据由此得到新的S—N曲线统计损伤,再结合室内等幅加载疲劳试验,建立室内外试验的当量关系。用传统修正Miner理论与低载强化理论分别对室外耐久性载荷谱进行损伤估计对比分析,验证弹簧的耐久性分析中低载强化的贡献大小。

Taking a car suspension spring as an object, the relationship between the indoor accelerated durability test and the durability mileage was studied to evaluate the spring＇s durability. After the combination of load spectrum from the strengthened Belgium road of the proving ground, the theory of low amplitude load strengthening was introduced in the process of the damage analysis. Considering the increase in fatigue strength due to the loads with strengthening effect below fatigue limit, the new S--N curve of the spring was obtained. Combining the statistical damage obtained from the new S--N curve with the indoor fatigue test under monotonic load, the equivalent relationship between indoor and outdoor tests was established. Through the comparison of damage estimates of outdoor durability load spectrum with traditional modified Miner＇s rule and low amplitude load strengthening theory, the contribution of the low amplitude load strengthening effort in the durability analysis of spring is verified. This study further broaden the scope of application of low amplitude load strengthening, and provide a technical reference for the durability evaluation of the auto parts.