基于应力能量方法分析膨胀聚乙烯的动态缓冲特性
Yueqing Xing1, Deqiang Sun1, Guoliang Chen1
1College of Bioresources Chemical and Materials Engineering (College of Flexible Electronics), Shaanxi University of Science & Technology, Xi'an 710021, China.
Polymers
|September 9, 2023
概括
本研究研究了扩展聚乙烯 (EPE) 泡的动态粉碎性能,使用冲击测试和应力能量方法. 结果显示,厚度和落下高度显著影响缓冲,有助于包装设计.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 聚合物科学 聚合物科学
背景情况:
- 扩展聚乙烯 (EPE) 被广泛用作缓冲材料.
- 了解其动态粉碎性能对于有效的包装设计至关重要.
- 现有的方法可能缺乏快速分析的速度或方便性.
研究的目的:
- 通过实验确定扩展聚乙烯 (EPE) 的动态破碎性能.
- 分析EPE厚度和降落高度如何影响其机械行为.
- 应用应力-能量方法来有效地表征缓冲特性.
主要方法:
- 在不同厚度和降落高度的EPE泡上进行了一系列动态冲击测试.
- 利用了压力-能量方法,涉及指数和多项式拟合,以建立动态压力和能量之间的关系.
- 确定缓冲材料常数 (a,b,c) 和分析的最大加速度-静态应力曲线.
主要成果:
- 增加EPE厚度导致动态缓冲性能曲线在相同的落下高度时有更大的开口.
- 较高的厚度导致最大加速度-静态应力曲线的最小点减少.
- 随着厚度的变化 (例如,在40mm下降时45.3%对于40mm而不是60mm) 和下降高度 (例如,在50mm厚度下降时93.3%对于600mm而不是300mm) 观察到最大加速的显著增加.
结论:
- 应力能量方法为EPE泡提供了一种快速方便的方法,以获得动态缓冲性能曲线,特别是当不需要高精度时.
- 厚度和降落高度是关键参数,可以显著改变EPE的动态机械行为和缓冲效果.
- 这些发现为优化EPE泡选择和设计在包装应用中提供了理论基础.
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