Material characterization and constitutive modelling of elastomers subject to strain rate

在汽车、航空航天和医疗部门的重要弹性体工程产品的设计中，使用寿命预测和保修考虑是两个重要的参数。橡胶部件在不同载荷和环境条件下的性能取决于弹性体在这些条件下的行为。橡胶的高度非线性行为是由其潜在的分子结构造成的，该分子结构由卷曲的长链聚合物组成。当材料被拉伸时，这些链条会伸直，并在卸载后回缩到其原始形状。这一基本现象导致了所观察到的橡胶的复杂力学行为，使其成为一种与载荷相关的材料。虽然对金属和塑料等材料的力学行为和预测进行了很好的研究，但对弹性体的分析和预测模型很少。这些模型大多只包含几个参数，并且依赖于应变水平和/或应变能密度。*拟议的研究计划将专注于开发一种新的弹性体本构模型，以考虑应变率效应和温度效应，从而更好地预测橡胶部件的性能。我们将进行一项全面的测试计划，其中将进行简单拉伸、纯剪切、双向拉伸和体积压缩测试，以确定弹性体在不同环境下的准静态和动态加载下的粘弹性性能。这一研究计划的结果将对汽车行业的先进材料和设计领域做出重大贡献。此外，拟议的工作将导致开发一种方法，专门用于工业应用和最重要的橡胶材料的开发和创新工程，来表征具有独特性能的弹性体。

Service life prediction and warranty consideration are two important parameters in the design of vital elastomeric engineering products for the automotive, aerospace, and medical sectors. The performance of rubber components under different loading and environmental conditions is dictated by the elastomer's behaviour under these conditions. The highly nonlinear behaviour of rubber is caused by its underlying molecular structure, which consists of coiled long-chain polymers. These chains straighten when the material is stretched and recoil to their original shape upon removal of the load. This fundamental phenomenon contributes to the observed complex mechanical behaviour of rubber, making it a load-dependent material. Although mechanical behaviour and predictions for materials such as metals and plastics are well researched, very few analyses and prediction models have been carried out for elastomers. Most of these models include only a few parameters and are dependent on strain levels and/or strain energy density.****The proposed research program will focus on developing a new constitutive model for elastomers to account for strain rate effects and temperature effects, leading to better performance prediction of rubber components. We will undertake a comprehensive testing program in which simple tension, pure shear, biaxial extension, and volumetric compression tests will be performed to determine the viscoelastic properties of elastomers under quasi-static and dynamic loadings in different environments. The findings of this research program will represent a major contribution to the area of advanced materials and design in the automotive industry. In addition, the proposed work will result in the development of a methodology to characterize elastomers with unique properties specifically for industrial applications and, most importantly, the development and innovative engineering of rubber materials.**