降低应力传播导致辅助性材料的机械故障阻力增加
1Department of Physics, Science Laboratories, Durham University, Durham DH1 3LE, United Kingdom.
概括
具有负波桑比率的辅助材料在塑性失效后表现出减少的应力传播. 这种特性增强了它们对机械故障和材料疲劳的抵抗力.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 固体力学 固体力学是什么
背景情况:
- 辅助性材料具有负波桑比率,在纵向拉伸时导致横向扩张.
- 实验研究表明,辅助性材料具有优越的性能,如增强的弹性和机械故障抵抗力.
- 对这些增强的机械性能,特别是抗故障性能的理论理解仍然有限.
研究的目的:
- 在局部塑性失效后,分析阐明辅助性材料中的应力传播.
- 以数值来证明减小应力传播对辅助性材料机械故障阻力的后果.
主要方法:
- 在塑料故障后空间应力传播的分析研究.
- 使用格子弹性塑料模型进行数值模拟.
主要成果:
- 与传统材料相比,辅助性材料的空间应力传播显著减少.
- 这种减少的应力传播限制了塑性失效引发后续事件的趋势.
- 数字模拟证实了对机械故障的抗性增加,这可以通过更高的产量应变和减少内部塑料损伤透来证明.
结论:
- 理论框架解释了辅助性材料增强的机械故障阻力.
- 减少应力传播被确定为辅助性材料优越性能背后的关键机制.
- 这些发现为设计具有更好的疲劳和故障特征的更坚固材料提供了基础.
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