在不同变形模式中的热积累及其与粘性弹性的相关性
Shouliang Nie1, Wei Huang1, Pengjie Ren2
1Center for Frontier Research & Technology, Zhongce Rubber Group Company Ltd., Hangzhou, Zhejiang, 310018, China.
Macromolecular rapid communications
|February 20, 2025
概括
材料中的热量积累对安全至关重要. 这项研究揭示了不同变形条件下的热生成与特定粘弹性质的相关性,提供了新的性能评估方法.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 机械工程 机械工程
背景情况:
- 材料在变形过程中的热积累 (HBU) 对产品性能和安全至关重要.
- 变形模式各不相同,导致HBU和材料粘性弹性之间存在复杂的相关性.
- 了解这种关系对于预测部件的行为至关重要.
研究的目的:
- 研究不同变形模式下的复合材料的热积累和粘弹性特性之间的相关性.
- 在变形过程中建立动态机械性能和热量产生之间的直接联系.
- 根据工作条件提出评估性能的新准则.
主要方法:
- 在复合材料上进行了应变和应力控制的热积累 (HBU) 实验.
- 使用动态机械分析仪 (DMA) 与样品温度测量单元.
- 同时监测动态机械性能和HBU以关联粘性弹性和热量产生.
主要成果:
- 在应变控制模式下,HBU与损失模量 (E) 线性相关.
- 在压力控制模式下,HBU与组合的风湿学参数 (例如,E"/E") 呈现线性相关性.
- 在歇斯底里循环中,分散能量密度 (Wdiss) 被确定为热量产生的主要来源.
结论:
- 该研究根据控制模式 (应变与应力) 提供了HBU和粘弹性参数之间的明显相关性.
- 拟议的指南建议将特定的粘弹性参数或它们的组合作为材料的性能指标.
- 这些发现使得更准确的性能评估能够根据特定的应用条件量身定制.
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