タイトル | Redesign of the mixed-mode bending test for delamination toughness |
著者(英) | Crews, J. H., Jr.; Reeder, J. R. |
著者所属(英) | NASA Langley Research Center |
発行日 | 1991-01-01 |
言語 | eng |
内容記述 | The mixed-mode bending (MMB) test uses a lever to simultaneously apply mode I and mode II loading to a split-beam specimen. A nonlinear, iterative analysis that accurately predicts the measured load-displacement response and the strain energy release rate, G, of an MMB test, has shown that the errors in G calculated using linear theory can be quite large. The nonlinear analysis was used as a guide in redesigning the MMB apparatus. With the redesigned apparatus, loads are applied through a roller attached to the lever and loaded just above the midplane of the test specimen. The redesigned MMB apparatus has geometric nonlinearity errors of less than 3 percent, even for materials substantially tougher than APC2 (AS4/PEEK). This apparatus was demonstrated by measuring the mixed-mode delamination fracture toughness of APC2. The data from the redesigned MMB apparatus were analyzed with a linear analysis which yielded results similar to those found with the original apparatus and the nonlinear analysis. |
NASA分類 | STRUCTURAL MECHANICS |
レポートNO | 92A32860 |
権利 | Copyright |
URI | https://repository.exst.jaxa.jp/dspace/handle/a-is/328136 |
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