高速冲击下子午线轮胎胎面胶的本构模型

摘要

在室温下,运用分离式 Hopkinson 压杆对子午线轮胎胎面胶进行高速冲击破坏试验(应变速率为2000~5400 s－1),得到了胎面胶在高速冲击下的应力-应变曲线；通过修正 Mooney-Rivlin 本构模型,构建了适用于高应变速率并具有脆性特征的动态本构模型,并通过非线性拟合得到了动态本构模型的拟合参数。结果表明：胎面胶呈现非线性应力-应变关系,屈服应力随应变速率的增加由89 MPa 增至345 MPa,具有应变速率强化效应与脆性断裂特征；本构模型计算得到的应力-应变与试验值比较吻合,验证了动态本构模型的可靠性。%At room temperature,high-speed impact destruction test was carried out for radial tyre tread compound by the split Hopkinson pressure bar apparatus at strain rate of 2 000-5 400 s-1 ,and stress-true strain curves were obtained at high-speed impact.A dynamic constitutive model used at high strain rate with brittle characteristics was built by modifying Mooney-Rivlin constitutive model,and the constitutive model parameters were obtained by nonlinear fitting.The results show that the tread compound presented nonlinear stress-strain relationship,the yield stress increased from 89 MPa to 345 MPa with the increase of strain rate,showing strain rate hardening effect and brittle fracture characteristic.The calculated true stress-true strain values were in good agreement with the experimental ones,this verfied the reliability of dynamic constitutive model.