由针织织物和软矩阵组成的复合材料. 我. 我. 我. 我. 我. 我. 我. 在课程方向上的裂增长
Fengkai Liu1, Xi Chen1, Zhigang Suo2
1State Key Lab for Strength and Vibration of Mechanical Structures, International Center for Applied Mechanics, Department of Engineering Mechanics, Xi'an Jiaotong University, Xi'an, China. tangjd@mail.xjtu.edu.cn.
Soft matter
|November 26, 2024
概括
这项研究研究了针织织物-弹性体复合材料的裂生长. 我们根据能量释放率发现了不同的裂纹行为,循环拉伸显著降低了线滑落和断裂的临界值.
科学领域:
- 材料科学 材料科学 材料科学
- 复合材料 复合材料 复合材料
- 机械工程 机械工程
背景情况:
- 结合织品和弹性体的复合材料具有独特的特性,如低刚性和高抗裂性.
- 应用包括先进的医疗设备,如心脏门和灵活的电子元件,如应变传感器.
研究的目的:
- 研究在单调和循环拉伸负荷下编织织物-弹性体复合材料中裂纹生长的机制.
- 为了确定控制裂传播,线滑落和线破裂的关键能量释放率.
主要方法:
- 使用尼龙编织织物和聚碳酸尿弹性体矩阵制造复合材料.
- 在预裂样本上进行了受控的单调和循环拉伸实验.
- 观察和分析裂纹的生长,子的行为 (滑动和破碎),以及能量释放率.
主要成果:
- 弹性体矩阵中的裂纹生长受的行为影响,特别是滑动和断裂.
- 确定了两个关键的能量释放率 (G_A和G_B),定义了不同的裂纹生长模式:没有增长,稳定增长与停止,和不稳定的增长.
- 在循环负荷下,观察到类似的裂行为,但关键能量释放率 (G_a和G_b) 比单调负荷要低得多.
结论:
- 这项研究阐明了针织织织物-elastomer复合材料中矩阵裂纹和强化行为之间的复杂相互作用.
- 了解这些关键的能量释放率对于设计用于需要高耐久性和灵活性的应用强大的材料至关重要.
- 循环负载条件对材料故障机制产生重大影响,需要针对这些场景量身定制的设计方法.
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