Corner fatigue cracking behavior of hybrid laser AA7020 welds by synchrotron X-ray computed microtomography
| Autor: | Jean-Yves Buffiere, Shengchuan Wu, Peishi Yu, L. Helfen, Y.N. Fu, Cheng Yu |
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| Rok vydání: | 2016 |
| Předmět: |
Materials science
business.industry Mechanical Engineering Laser beam welding Fracture mechanics 02 engineering and technology Welding Structural engineering Plasticity 021001 nanoscience & nanotechnology Condensed Matter Physics law.invention Cracking Crack closure 020303 mechanical engineering & transports Fracture toughness 0203 mechanical engineering Mechanics of Materials law mental disorders General Materials Science Composite material 0210 nano-technology business Stress concentration |
| Zdroj: | Materials Science and Engineering: A. 651:604-614 |
| ISSN: | 0921-5093 |
| DOI: | 10.1016/j.msea.2015.11.011 |
| Popis: | To elucidate the fatigue corner cracking behaviors related with gas pores of hybrid laser arc welded 7020–T651 alloys, both high-resolution in situ synchrotron X-ray computed microtomography and finite element based predictions containing the closure effect or significant plasticity have been undertaken in the domain of fracture mechanics. It is found that fatigue cracks are preferentially initiated from a pore intersecting with the corner free surface and that it steadily propagates inside the weld with a quarter elliptical shape. Moreover, the fatigue corner crack exhibits a very complex morphology. A quantitative agreement between the experiment and prediction of crack shape under executed loading cycles is observed. By using the critical stress intensity factor along the crack line, the modified fracture toughness of a given hybrid laser weld can also be determined numerically for three-dimensional non-penetration curved fatigue cracks. |
| Databáze: | OpenAIRE |
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