脂肪尾故障强度分布和制造缺陷在先进的复合材料中的缺陷
1College of Engineering and Applied Science, University of Wisconsin-Milwaukee, 3200 N Cramer St, Milwaukee, WI, 53211, USA. elhajjar@uwm.edu.
Scientific reports
|July 17, 2025
概括
碳纤维复合材料的制造缺陷大大改变了故障模式,从可预测的分布转变为高度可变的,脂肪尾的分布. 这就需要对安全关键应用进行先进的风险评估.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 可能性理论概率理论.
背景情况:
- 碳纤维增强聚合物复合材料在苛刻的应用中至关重要.
- 了解故障机制对于结构完整性和安全至关重要.
- 制造缺陷可以显著影响复合材料的性能.
研究的目的:
- 调查制造缺陷对复合材料故障统计分布的影响.
- 分析像孔隙性和纤维波动性这样的缺陷如何在张力和压缩下改变强度分布.
- 评估这些变化的分布对风险管理和设计的影响.
主要方法:
- 具有和没有缺陷的张力和压缩样本的分析.
- 对强度分布的统计检查,包括概率密度.
- 应用詹森不等式来评估可变性和风险概况.
主要成果:
- 没有缺陷的复合材料显示了狭窄的单模强度分布.
- 有缺陷的复合材料 (多孔性,纤维波纹性) 呈现多式模式,脂肪尾分布.
- 缺陷导致更高的可变性和改变的统计失败行为.
结论:
- 制造缺陷从根本上改变了复合材料故障的统计性质.
- 由于缺陷而增加的可变性需要复杂的概率设计方法.
- 在安全关键的应用中,准确的风险管理取决于了解复合材料故障的尾部风险.
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