使用数字图像相关性对疲劳裂生长的非线性参数的实验评估
Giancarlo L Gómez Gonzales1, Francisco A Díaz1
1Department of Mechanical and Mining Engineering, University of Jaén, 23071 Jaén, Spain.
Materials (Basel, Switzerland)
|November 27, 2025
概括
这项研究引入了一种高分辨率的数字图像相关性 (DIC) 方法来分析裂尖的可塑性. 这些发现显示了塑料裂尖开口位移 (CTODp) 和疲劳裂生长之间的强烈相关性,验证了生命评估的技术.
科学领域:
- 材料科学与工程 材料科学与工程
- 机械工程 机械工程
- 断裂力学 断裂力学 断裂力学
背景情况:
- 精确地描述裂尖区域对于理解疲劳裂传播至关重要.
- 传统方法往往缺乏精确测量裂纹尖端小规模塑料变形的分辨率.
- 非线性参数,如塑料裂尖开口位移 (CTODp) 和周期性塑料区域大小,是疲劳行为的关键指标.
研究的目的:
- 通过使用数字图像相关性 (DIC) 对裂尖区域进行高分辨率特征的实验方法.
- 评估非线性参数 (CTODp,周期性塑性区域大小) 与疲劳裂传播之间的相关性.
- 为了验证在复杂负载下对疲劳寿命评估的拟议的DIC方法.
主要方法:
- 使用立体显微镜设置进行高分辨率成像.
- 采用3D数字图像相关性分析 (DIC) 进行精确的裂纹尖端测量.
- 在AISI 1020钢的紧张试样上进行了恒定-ΔK疲劳测试.
主要成果:
- 在CTODp,周期性塑性区域大小和稳定的疲劳裂传播之间显示出强烈的相关性.
- 通过一致的结果验证了拟议的高分辨率DIC方法.
- 在测试条件下,验证了裂尖的可塑性对疲劳裂生长的意义.
结论:
- 开发的高分辨率DIC方法有效地表征了裂纹尖端可塑性.
- CTODp和周期性塑料区大小是疲劳裂传播的可靠指标.
- 该方法在复杂的负载场景中对疲劳寿命评估具有实用性.
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