乙烯乙酸乙烯 (EVA) 泡的一维动态构成模型
Jin Wu1, Fude Lu1, Jiaxuan Chen1
1School of Packaging and Material Engineering, Hunan University of Technology, Zhuzhou 412007, China.
Polymers
|January 17, 2024
概括
乙烯乙酸共聚合物 (EVA) 泡的强度随着由于被困空气而导致的更高的应变率而增加. 这项研究开发了一种模型,以了解撞击保护材料中的这种取决于速率的行为.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物工程 聚合物工程
- 材料机械学 材料机械学
背景情况:
- 乙乙酸乙烯共聚物 (EVA) 是一种速度敏感的材料,以冲击保护和能量吸收而闻名.
- 在动态负载下了解EVA泡的机械行为对于优化其性能至关重要.
- 被困空气和延展率对泡强度的影响需要进一步研究.
研究的目的:
- 为了研究增加的拉伸率和被困空气如何影响EVA泡的强度增强.
- 为EVA泡的大型变形反应开发一个一维的动态构成模型.
- 量化空气泄漏,延展率和材料行为之间的关系.
主要方法:
- 在0.0017/s,0.033/s和0.17/s的应变速率下对EVA泡压缩变形进行实验性调查.
- 开发一个包含材料和气压组件的动态构成模型.
- 准静态和动态压缩试验以确定模型参数 (a1,a2,泄漏率 δ).
- 使用ORIGIN软件进行数据拟合,以获得构成模型参数.
主要成果:
- 空气泄漏率与应变率的比率随着应变率的增加而下降.
- 在较高的张力率下,空气会越来越多地被困在EVA泡细胞内.
- 这种空气捕获有助于观察到泡材料强度的增强.
结论:
- 开发的动态构成模型准确地描述了EVA泡的大变形行为.
- 延展率的增加导致空气逃逸减少,并且由于空气陷而提高材料强度.
- 研究结果为优化EVA泡的应用提供了洞察力,这些应用需要优质的冲击保护.
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