一个多尺度模型,用于预测金属的物理短裂和长裂行为
Xing Yang1, Chunguo Zhang1, Panpan Wu1
1Key Laboratory of Highway Construction Technology and Equipment of the Ministry of Education, Chang'an University, Xi'an 710064, China.
Materials (Basel, Switzerland)
|November 9, 2024
概括
这项研究引入了一种多尺度疲劳裂增长模型,以预测金属疲劳行为. 该模型准确地预测了裂生长率和疲劳寿命,与短期和长期裂的实验数据保持一致.
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:
- 金属的疲劳行为是复杂的,受到缺陷,材料特性和加载条件的影响.
- 了解疲劳裂的发起和传播对于结构完整性和部件寿命至关重要.
- 现有的模型往往难以准确地捕捉从物理短裂 (PSC) 到长裂 (LC) 的过渡.
研究的目的:
- 开发和验证一个新的多尺度疲劳裂生长模型.
- 准确预测在单轴负荷下金属标本的裂纹生长率和疲劳寿命.
- 将材料异质性和实验散射纳入疲劳寿命预测中.
主要方法:
- 开发一个综合物理短裂 (PSC) 和长裂 (LC) 行为的多尺度模型.
- 根据材料特性,样本几何形状和应力比率计算裂纹生长率.
- 整合高斯分布理论来解释材料异质性和实验错误.
- 预测裂纹生长率和疲劳寿命的标本与不同的口几何形状.
主要成果:
- 多尺度模型成功预测了金属标本的裂生长率和疲劳寿命.
- 模型预测显示,PSC和LC阶段的实验数据与已发表文献中的实验数据一致.
- 该模型有效地解释了材料特性,几何形状和加载条件对疲劳行为的影响.
结论:
- 开发的多尺度疲劳裂增长模型为预测金属疲劳提供了一个强大的框架.
- 该模型能够整合材料异质性和实验散射的能力提高了其预测准确性.
- 这种方法为设计和评估金属元件在工程应用中的耐用性提供了宝贵的见解.
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