承受应力扭转负荷的VO-:在聚合物样本上的实验和理论断裂研究
Hossein Talebi1, Mohsen Askari1, Majid Reza Ayatollahi1
1Fatigue and Fracture Research Laboratory, Center of Excellence in Experimental Solid Mechanics and Dynamics, School of Mechanical Engineering, Iran University of Science and Technology, Tehran 16846, Iran.
Polymers
|June 10, 2023
概括
这项研究调查了具有V形口和端孔 (VO口) 的脆性材料的断裂行为. 新的标准准确地预测了这些复杂几何形状的断裂阻力,有助于材料设计.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 断裂力学 断裂力学 断裂力学
背景情况:
- 易碎的材料容易破裂,特别是当它们被几何不连续性削弱时.
- 了解具有V形口和端孔 (VO口) 的组件的断裂行为对于结构完整性至关重要.
研究的目的:
- 在实验和理论上研究具有VO痕的脆弱标本的骨折行为.
- 为了评估口末孔大小对断裂阻力的影响.
- 开发和验证基于应力标准,用于预测混合模式负载下的VO断组件的断裂.
主要方法:
- 在各种混合模式负载条件下 (I,III和组合) 对VO标记的PMMA样本进行实验测试.
- 系统地改变隙末孔半径 (1,2,4毫米),以评估几何效应.
- 开发和应用最大触角应力 (MTS) 和平均应力 (MS) 标准,用于VO-notches.
- 理论预测与实验骨折数据的比较.
主要成果:
- 实验数据揭示了VO和末孔大小对骨折行为的影响.
- 开发的VO-MTS和VO-MS标准是为混合模式I/III负载建立的.
- 在VO-MTS标准预测骨折阻力与大约92%的准确度.
- VO-MS标准在预测骨折耐力方面达到约90%的准确性.
结论:
- 这项研究成功地描述了VO-notched脆标本的骨折行为.
- 开发的VO-MTS和VO-MS标准为这些几何形状中的断裂条件提供了可靠的预测.
- 这些标准提高了估计断裂阻力的能力,有助于更安全的材料设计和应用.
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