在经过应变诱导结晶的双轴拉伸弹性体中进行应变硬化
Soichiro Hiraiwa1, Thanh-Tam Mai1, Katsuhiko Tsunoda2
1Department of Material Chemistry, Kyoto University Nishikyo-ku Kyoto 615-8510 Japan urayama.kenji.2s@kyoto-u.ac.jp.
RSC advances
|November 29, 2023
概括
在平面延伸下,由于应力诱导结晶 (SIC),在天然 (NR) 和合成异烯 (IR) 中观察到应力硬化. 这种对材料性能至关重要的现象发生在特定的拉伸值,影响应力分布和机械行为.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物物理 聚合物物理
- 机械工程 机械工程
背景情况:
- 应变诱导结晶 (SIC) 是自然 (NR) 和合成异烯 (IR) 等弹性体应变硬化的关键机制.
- 在双轴应力状态下理解SIC对于预测真实应用中的部件性能至关重要.
- 平面延伸,一种特定的双轴变形,与单轴延伸相比,为研究SIC提供了独特的条件.
研究的目的:
- 在平面延伸下,在NR和IR中研究和揭示由SIC驱动的应变硬化.
- 为了确定平面延伸期间SIC发病的临界拉伸值.
- 分析这些在应变硬化体制中的应力分布和机械反应.
主要方法:
- 在精确形状的样上使用定制的双轴拉伸测试仪进行平面延伸测试.
- 采用广角X射线散射 (WAXS) 来识别应变诱导结晶 (SIC) 的开始阶段.
- 测量和分析拉伸和约束方向的标称应力,作为拉伸比率的函数.
主要成果:
- 由于SIC超出平面延伸的临界延伸 (λc),在NR和IR中观察到显著的应变硬化.
- 在平面延伸中确定SIC发病的临界延伸 (λc),并发现与观察到的应变硬化保持一致.
- 在λc附近注意到应力比率 (σy/σx) 的明显最低值,表明不同方向应力贡献的变化.
结论:
- 应变诱导结晶 (SIC) 在平面延伸下的NR和IR中有效诱导应变硬化.
- 平面延伸中SIC的临界延伸略低于单轴延伸,由机械工作考虑来解释.
- 这项研究为弹性体的双轴机械行为提供了关键的见解,有助于预测材料性能.
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