温度,速率和分子量对软块共聚 ((乙-乙)) 热塑性弹性体的故障行为的影响
Simone Sbrescia1, Jianzhu Ju2, Costantino Creton2
1Bio and Soft Matter Division (BSMA), Institute of Condensed Matter and Nanosciences (IMCN), Universite Catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium. enomissbrescia@gmail.com.
Soft matter
|June 30, 2023
概括
热塑性弹性体 (TPEs) 在温度或变形速率的微小变化下,在断裂和疲劳行为中呈现急剧的转变. 了解这种复杂的速率依赖对于设计耐用TPE元件至关重要.
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:
- 热塑性弹性体 (TPE) 是多用途的工程聚合物,因其灵活性,耐用性和可回收性而受到重视,作为耐热的可持续替代品.
- 虽然研究了它们的高温机械性能,但它们的骨折和疲劳行为,特别是在不同的条件下,仍然不太了解.
- 使用TPE进行设计需要深入了解温度和变形速率如何影响其故障机制.
研究的目的:
- 为了研究基于模块共聚 (-) 的TPEEs的骨折和疲劳行为.
- 分析温度,变形速率和分子重量对TPE故障机制的影响.
- 为了合理化TPE中观察到的复杂的速度依赖失效行为.
主要方法:
- 在广泛的温度和变形速度范围内评估TPEE的拉伸,断裂和疲劳性能.
- 使用数字图像相关性 (DIC) 来测量过程区域的大小和时间依赖性.
- 对软,弹性和坚固材料的微机械模型进行比较.
主要成果:
- 从抗口到对口敏感行为的急剧过渡,观察到温度或速率的轻微变化.
- 疲劳裂纹传播在值应变以下被抑制,变形率的增加在断裂测试中降低了性,但在拉力测试中增加了性.
- 应变和应力移位被确定为高性的关键因素,具有很强的分子重量依赖.
结论:
- TPE的故障行为对负载条件 (温度,速度,应变) 非常敏感.
- 在拉力与断裂测试中观察到的取决于速率的差异是由应力场和材料粘性弹性的变化解释的.
- 了解压力转移和故障核化的特征时间对于预测TPE速率依赖至关重要.
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