Visualization of strain distribution around fatigue crack developed by low cycle fatigue test in high-strength steels using digital image correlation method for replica films

Portable electronics devices such as mobile phone and portable music player become compact and improve their performance. High-density packaging technology such as CSP (Chip Size Package) and Stacked-CSP is used for improving the performance of devices. CSP has a bonded structure composed of materials with different properties. A mismatch of material properties may cause stress singularity, which lead to the failure of bonding part in structures. In the present study, a strain singular field near inter-face edge in three-dimensional joints is investigated using digital image correlation method. A specimen which silicon chip was embedded in resin is used in experiment and tensile load is applied to the specimen. Photograph of specimen surface is taken before and after loadings by laser microscope. Displacement on the surface was evaluated by the digital image correlation method (DICM) using data of surface pattern on the specimen, which the cross correlation coefficients for surface pattern are maximized. Strain on surface of specimen is calculated by using the moving least square method. On the other hand, 3D element free Galerkin method is applied to compute the displacement and strain distribution in a three-dimensional model of the specimen. In the element free Galerkin method, the physical values, i.e., displacement, strain and stress, can be obtained by using the displacement data at node. In this research, strain distribution near the edge of interface is computed based on the element free Galerkin method. Finally, the strain distribution obtained by the digital image correlation method and the moving least square method is compared with that obtained by the element free Galerkin method. The intensity of strain singularity is determined numerically and experimentally.

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Effect of Hydrogen on Deformation Behavior of Carbon Steel S25C —Measurement of Time Evolution of Strain Distribution until Crack Initiation Using Digital Image Correlation Method—

ISIJ International ◽

10.2355/isijinternational.54.1965 ◽

2014 ◽

Vol 54 (8) ◽

pp. 1965-1970 ◽

Cited By ~ 2

Author(s):

Shinnosuke Aomatsu ◽

Ryosuke Matsumoto

Keyword(s):

Carbon Steel ◽

Digital Image Correlation ◽

Crack Initiation ◽

Time Evolution ◽

Digital Image ◽

Deformation Behavior ◽

Strain Distribution ◽

Correlation Method ◽

Image Correlation ◽

Digital Image Correlation Method

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Determination of opening stresses for railway steel under low cycle fatigue using digital image correlation

Theoretical and Applied Fracture Mechanics ◽

10.1016/j.tafmec.2020.102601 ◽

2020 ◽

Vol 108 ◽

pp. 102601 ◽

Cited By ~ 1

Author(s):

Ans Al Rashid ◽

Ramsha Imran ◽

Muhammad Yasir Khalid

Keyword(s):

Digital Image Correlation ◽

Digital Image ◽

Low Cycle Fatigue ◽

Image Correlation ◽

Cycle Fatigue

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Research on the Surface Deformability of Reinforced Concrete Beams with the Use of Digital Image Correlation Method

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.240.25 ◽

2015 ◽

Vol 240 ◽

pp. 25-30

Author(s):

Rafal Ostromecki ◽

Karol Suprynowicz

Keyword(s):

Reinforced Concrete ◽

Digital Image Correlation ◽

Digital Image ◽

Strain Distribution ◽

Concrete Beams ◽

Concrete Structures ◽

Correlation Method ◽

Reinforced Concrete Beams ◽

Image Correlation ◽

Digital Image Correlation Method

The results of experimental research on a single span reinforced concrete beams are presented in the paper. The study was undertaken to explain some issues, amongst which the most important one was the recognition of strain distribution in the shear zone of RC beams. It was decided to adopt the modified Digital Image Correlation Method (DIC) and the software created by K. Suprynowicz to follow the surface deformations. This was the first application of the software to the concrete structures behaviour analysis. Hence, another aim of the study was to confirm the proper susceptibility and usefulness of this tool for further research on concrete elements. What’s more the scope of the software future development was defined, that would allow for observation of some particular phenomena characteristic for concrete, like cracking. Finally, the conclusion is presented, that application of the proposed variant of DIC method to concrete structures is promising, although for the recognition of shear strain distribution it requires increasing the accuracy by increasing spatial resolution of images and modifications of the software.

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