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人类头发的疲劳失效测试:用于常压实验的韦布尔分析
Leila Berriche1, Jessica Welzel2, Svitlana Sirenko3
1Henkel Consumer Brands, Henkel AG &Co KGaA, D-22761, Hamburg, Germany; Department of Chemistry, University of Hamburg, D-20146, Hamburg, Germany.
Journal of the mechanical behavior of biomedical materials
|December 5, 2024
概括
这项研究研究了循环应变下的人类头发疲劳失败,使用韦布尔分布分析. 结果显示,应变显著影响头发.
科学领域:
- 材料科学 材料科学 材料科学
- 生物力学 生物力学
- 织科学 织科学
背景情况:
- 疲劳失效测试对于循环负荷下的材料耐用性至关重要.
- 人类头发受到长期的,振荡式的压力和应变.
- 现有的研究主要集中在持续应力疲劳测试上.
研究的目的:
- 为了研究人类头发疲劳失败在各种恒定的压力水平下.
- 为了补充现有的疲劳测试数据与恒定应变实验.
- 分析疲劳行为使用累积的两参数韦布尔分布 (CWD) 的非线性适合.
主要方法:
- 对人类头发进行了循环疲劳测试,持续应力水平在4%至30%之间.
- 将累积的双参数韦布尔分布 (CWD) 适用于生存数据的非线性匹配.
- 分析数据使用寿命指数 (ln) 和形状因子 (β) 为关键参数.
主要成果:
- 高的确定系数和正常分布的残余值表明了精确的参数值.
- 由于数据分组,参数值的精度在高常量应变下降.
- 寿命指数 ln(α) 降低,形状因子β随着应变而呈指数增长.
- 当β在4.3%应变时超过统一时,观察到故障模式的根本变化.
- 理论曲线的ln(α) 和β穿过约45%的应变,与传统的拉力断裂应变对齐.
结论:
- 累积的双参数韦布尔分布 (CWD) 有效地模拟了人类头发疲劳失败数据.
- 应变显著影响人类头发的疲劳寿命和故障模式.
- 这些发现表明CWD模型在头发疲劳分析中的非实证依据.
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