Development of optical multi-scale strain distribution measurement method and experimental elucidation of damage mechanism

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K05996
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Materials/Mechanics of materials
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: Ri Shien 国立研究開発法人産業技術総合研究所, 計量標準総合センター, 主任研究員 (70509710)
• Co-Investigator(Kenkyū-buntansha): 王 慶華 国立研究開発法人産業技術総合研究所, 計量標準総合センター, 主任研究員 (20726856)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 光学的手法 / モアレ計測 / マルチスケール / ひずみ分布 / サンプリングモアレ / 位相解析

Outline of Final Research Achievements

In this research, we develop an optical multi-scale displacement/strain measurement method using phase analysis technology of moire phenomenon and fringe image and try to clarify the mechanism of damage in CFRP composite materials and dissimilar structural materials by an experimental approach. In order to perform the multi-scale measurement, a multi-scale grating mold was fabricated, in which a small grating of 750 nm pitch and a large grating of 15-micron pitch were mixed. We have developed a two-pixel sampling moire method that can measure deformation with a wider field of view and a two-way simultaneous analysis method of a two-dimensional grid that can measure strain with high accuracy. By applying these methods to the 3-point bending test of CFRP composites, we could realize the measurement of normal and shear strain distributions with high accuracy.

Free Research Field

実験力学

Academic Significance and Societal Importance of the Research Achievements

航空機や自動車などで使われる炭素繊維強化プラスチック（CFRP）は金属材料と異なり、炭素繊維と樹脂の複合材料であるゆえに複雑な変形挙動と破壊モードを示す。そのためミクロからマクロまでの一連の変形挙動を把握する必要がある。本研究は全視野かつ異なるスケールで同時に評価可能なマルチスケールひずみ分布を測定できる光学的手法を開発した。本開発技術はCFRP複合材や半導体チップ等の異種材料間での損傷メカニズムの解明に役立つ計測技術である。