丁羟包覆层的黏超弹本构模型

Visco-hyperelastic constitutive model of hydroxyl-terminated polybutadiene inhibitor

为了准确地描述丁羟(HTPB)包覆层在有限变形下的拉伸力学特性,研究了HTPB包覆层的黏超弹本构模型。分别构建了含率相关函数的本构模型和并联式本构模型,前者由超弹模型与率相关项相乘得到,后者由超弹模型与含损伤因子的黏弹模型并联而成。进行了HTPB包覆层的单步松弛、多步松弛和不同速率的单轴拉伸试验,并将试验数据用于拟合模型参数。结果表明,HTPB包覆层对应变率极其敏感,且具有很大的延伸率,表现出明显的黏超弹特性;两种模型均能很好地预测HTPB包覆层较大形变范围内的拉伸力学性能,其中含率相关函数的模型的描述更加准确,其研究具有重要的军事意义。

The visco-hyperelastic constitutive models of hydroxyl-terminated polybutadiene(HTPB)inhibitor were studied to describe the tensile mechanical properties accurately under finite deformation.Visco-hyperelastic constitutive model with rate related function and parallel constitutive model were built respectively,and the first model was multiplicatively combined by hyper-elastic model and rate related function,while the latter model was parallelly formed by hyper-elastic model and viscoelastic model containing damage factor.In order to fit the model parameters by the test data,the single-step relaxation test,multi-step relaxation test and uniaxial tensile test at various rates of HTPB inhibitor were undertaken.The results show that HTPB inhibitor is extremely sensitive to strain rate and has a great elongation,reflecting the obvious visco-hyperelasticity.Both of the models are able to predict the tensile mechanical properties of HTPB inhibitor in a large deformation range,meanwhile the model with rate related function can describe the mechanical properties more precisely,which is of great military significance.