Development of Evaluation Method for Fatigue Damage in Metal Materials Using Laser Speckle

激光散斑金属材料疲劳损伤评价方法的研制

• 批准号: 12650099
• 负责人: KATO Akira
• 金额: $ 2.18万
• 依托单位: Chubu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12650099/
• 关键词: Optical Measurement; Fatigue; Non-Destructive Testing; Fatigue Life Estimation; Image Processing; Steels

In this study, a Method is investigated to detect change in surface properties of metal materials and to estimate fatigue life during fatigue loading using optical method. Results derived from this study are shown below.(1)We investigated change of surface properties depending on increase of loading cycles under constant stress amplitude. We considered mathematical mean roughness and Fractal dimension and spatial frequency distribution of surface profiles as surface properties. Relation between these parameters and number of loading cycles were investigated. It was clarified that these surface parameters changes depending on number of loading cycles and there is a correspondence between surface properties and fatigue damage.(2)Relation between width of laser speckle pattern and number of loading cycles was investigated. Among surface properties and width of speckle pattern, spatial frequency distribution is related the most to width of speckle pattern. Width of speckle pattern has the best correlation with number of loading cycles and it was concluded that width of the speckle pattern is the most appropriate as a parameter to evaluate fatigue damage.(3)We developed an optical setup to observe speckle pattern formed by the reflected light when a He-Ne laser illuminates the object and observe speckle pattern on site during working of the testing machine.(4)We derived an experimental equation, which expresses the relation between a parameter of the speckle pattern and number of loading cycles for different stress amplitudes. We also construct the database of relations between a parameter of the speckle pattern and stress amplitude and relation between change rate of the speckle pattern and fatigue life. We devised a method to estimate fatigue life during working object based on the experimental equation and the database. Fatigue life estimation was tried using this method and the result showed that this method has a possibility for practical use.

在本研究中，探讨一种利用光学方法侦测金属材料表面性质变化，并评估疲劳寿命的方法。本研究的结果如下所示。(1)We研究了在恒定应力幅下，随着加载循环次数的增加，表面性质的变化。我们认为数学平均粗糙度和分形维数和表面轮廓的空间频率分布作为表面特性。研究了这些参数与加载循环次数之间的关系。结果表明，这些表面参数的变化取决于加载循环次数，表面性能和疲劳损伤之间存在对应关系。（2）研究了激光散斑宽度与加载循环次数的关系。在表面特性和散斑宽度中，空间频率分布与散斑宽度的关系最大。散斑图宽度与加载循环次数的相关性最好，可以得出结论，散斑图宽度是最适合作为评估疲劳损伤的参数。(3)We研制了一套观察He-Ne激光照射物体时反射光形成的散斑图的光学装置，并在试验机工作过程中现场观察散斑图。(4)We导出了不同应力幅下散斑图参数与加载循环次数的关系式。建立了散斑图参数与应力幅值关系、散斑图变化率与疲劳寿命关系的数据库。设计了一种基于实验方程和数据库的疲劳寿命估算方法。利用该方法对疲劳寿命进行了估算，结果表明该方法具有实用价值。

项目成果

Akira Kato, Fumihiko Okuya: "Evaluation of fatigue damage using laser speckle(Relation between surface profile and diffraction pattern)"Proceedings of SPIE. Vol.4317. 374-379 (2001)

加藤彰、奥谷文彦：“利用激光散斑评估疲劳损伤（表面轮廓与衍射图案之间的关系）”SPIE 论文集。

Akira Kato, Hisanao Wate: "Deformation Measurement Using Digital Image Correlation (Interpolation method for sub-pixel accuracy)"Proceedings of APCFS & ATEM 01. 840-845 (2001)

Akira Kato、Hisanao Wate：“使用数字图像相关的变形测量​​（亚像素精度的插值方法）”APCFS 论文集

Akira Kato, Mitsue Hayashi: "A New Method for Fatigue Life Estimation of Steels, Technology, Law and Insurance"The Journal of the International Society for Technology, Law and Insurance. Vol.5,No.1/2. 9-14 (2000)

Akira Kato、Mitsue Hayashi：“钢材、技术、法律和保险疲劳寿命估算的新方法”国际技术、法律和保险学会杂志。

Akira Kato, Tsuyoshi Yoshitomi, Yoshiomi Shibata: "Parallel Processing of Finete Element Method Using Domain Decomposition Method (On the Parameter Setting for Convergence of Boundary Conditions)"J.Japan Society for Design Engineering (in Japanese). Vol.3

Akira Kato、Tsuyoshi Yoshitomi、Yoshiomi Shibata：“使用域分解法的细元法并行处理（关于边界条件收敛的参数设置）”J.日本设计工程学会（日文）。

Akira Kato, Fumihiko Okuya: "Evaluation of fatigue damage using laser speckle(Relation between surface profile and diffraction pattern)"Proceedings of SPIE. 4317. 374-379 (2001)

加藤彰、奥谷文彦：“利用激光散斑评估疲劳损伤（表面轮廓与衍射图案之间的关系）”SPIE 论文集。