Material characterization and constitutive modelling of elastomers subject to strain rate

使用寿命预测和保修考虑是汽车、航空航天和医疗领域重要弹性体工程产品设计中的两个重要参数。橡胶部件在不同负载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基本分子结构引起的，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，并在去除负载后恢复到原来的形状。这一基本现象有助于观察到橡胶的复杂机械行为，使其成为一种依赖于载荷的材料。尽管对金属和塑料等材料的机械行为和预测进行了深入研究，但对弹性体的分析和预测模型却很少。这些模型中的大多数仅包含几个参数，并且取决于应变水平和/或应变能密度。****拟议的研究计划将重点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。我们将进行全面的测试计划，其中将进行简单拉伸、纯剪切、双轴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载荷下的粘弹性能。该研究项目的研究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来表征具有独特性能的弹性体，专门用于工业应用，最重要的是，橡胶材料的开发和创新工程。 **

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.**