在冲击下,封闭细胞PVC泡的应变率灵敏度和构成定律
Materials (Basel, Switzerland)
|July 29, 2023
概括
这项研究以数值方式研究了受冲击的PVC泡的应变速率影响. 基本材料的基础材料.
科学领域:
- 材料科学 材料科学 材料科学
- 计算力学 计算力学 计算力学
- 聚合物物理 聚合物物理
背景情况:
- 闭细胞PVC泡在冲击负荷下表现出复杂的行为.
- 了解应变速率的依赖性和气体效应对于预测泡性能至关重要.
- 现有的模型可能无法完全捕捉这些合现象.
研究的目的:
- 为了数值地研究受冲击的封闭细胞PVC泡的应变率依赖性.
- 阐明基础材料延展率效应和被困气体效应的不同作用.
- 提出和比较冲击载荷PVC泡的组成模型.
主要方法:
- 一个基于细胞的模型被开发出来,并与合欧利尔-拉格兰 (CEL) 方法集成.
- 数字模拟的重点是基材的延展率效应和被困气体效应.
- 提出并比较了两个宪法,一个是基于Hugoniot关系的,另一个是基于D-RPH模型的.
主要成果:
- 基材的拉伸率显著影响应力大小和拉伸分布.
- 捕获的气体主要影响速度场,并显著减少冲击应变.
- 对于PVC泡 (相对密度为0.07),基材拉伸率增加了45%的冲击应力,减少了0.04的拉伸,而气体则减少了0.18的拉伸.
结论:
- 基本材料的拉伸率和被困气体效应对于在冲击下的PVC泡的准确建模至关重要.
- 拟议的构成模型为预测PVC泡在动态负载下的行为提供了基础.
- 该研究强调了考虑这些合效应对材料设计和应用的重要性.
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