预测使用有限断裂力学使用热负荷诱导的自由边缘脱层
Mohammad Burhan1, Zahur Ullah1,2, Zafer Kazancı1
1Advanced Composites Research Group, School of Mechanical and Aerospace Engineering, Queen's University Belfast, Ashby Building, Belfast, Northern Ireland BT9 5AH UK.
概括
这项研究应用了有限断裂力学 (FFM) 来预测在热负荷下角度层层材中的分层. 这种新的方法准确地预测了裂的开始,提高了复合材料的耐用性.
科学领域:
- 复合材料科学 复合材料科学
- 机械工程 机械工程
- 断裂力学 断裂力学 断裂力学
背景情况:
- 层复合材料中的材料不匹配会导致自由边缘的层间应力.
- 这些压力可能导致过早的层间裂和故障.
研究的目的:
- 应用有限断裂力学 (FFM) 来预测角度层层材的自由边缘分层.
- 在热负荷下,在不相似的接口上开发一个3DFFM裂核的标准.
主要方法:
- 通过使用维度分析和有限元模型,半分析地确定层间应力和能量释放率.
- 实现3DFFM标准,通过被约束的非线性优化解决,假设同质裂纹延伸.
- 使用临界距离理论 (TCD) 验证和与现有文献模型进行比较.
主要成果:
- 来自应力和能量释放率的非尺寸化函数,独立于热负荷和层厚度.
- 3D FFM 方法准确地预测了自由边缘分层.
- 对FE模型进行了文献验证,对数值解决方案进行了维度分析.
结论:
- 开发的3D FFM框架提供了一种有效和准确的方法来预测复合板材中的分层.
- 这项研究证明了FFM和TCD在分析热应力下的角度层层材的复杂断裂行为方面的有效性.
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