摘要
对由汽车橡胶隔振器常见的橡胶材料制作的哑铃形圆柱试件,进行不同应变比R下的疲劳试验,并分析应变比R对疲劳寿命的影响。以应变峰值、应变幅值为损伤参量,建立相应的疲劳寿命预测模型,并对R 0、R<0两种工况下模型的预测结果进行比较。结果表明,当R 0时二种模型都有较高的预测精度,而在R<0的载荷工况下,R对用应变幅值为损伤参量的预测模型的预测精度影响较大,为此建立考虑应变比R效应的等效应变幅值,并以此为损伤参量建立R<0的寿命预测模型,该模型预测的寿命与实测寿命的偏差均在2倍分散因子之内,相关系数提高到0.9231。所得到的填充天然橡胶材料的疲劳寿命预测模型,可为橡胶隔振器前期耐久性结构设计提供参照。
Under various strain ratios R loads, a uniaxial fatigue experiment is carried out for a dumbbell cylindrical specimen of filled natural rubbers used in automotive rubber isolators. Based on the measured fatigue data, the effect of R on fatigue life is discussed and two fatigue prediction models are established. The model I is based on the damage parameter of strain peak, and the model II is based on the damage parameter of strain amplitude. It is concluded that both the two models are appropriate for predicting fatigue life under R~〉0 loading conditions, while under R〈0 loading conditions the model II can＇t be used for predicting fatigue life of filled natural rubbers. An equivalent strain amplitude is proposed as a damage parameter for predicting fatigue life under R〈0 loading conditions. The predicted fatigue life using the proposed equivalent strain amplitude as the damage parameter is in a good agreement with the experimental fatigue life within a factor of two, and with an improved correlation coefficient of 0：923 1. The proposed model for fatigue life prediction with the equivalent strain amplitude can be used to estimate the fatigue life for a rubber component with filled natural rubbers for any strain ratio.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2013年第8期49-56,共8页
Journal of Mechanical Engineering
基金
国家自然科学基金资助项目(51275175)
