A white light speckle method applied to the determination of stress intensity factor and displacement field around a crack tip
✍ Scribed by F.P. Chiang; A. Asundi
- Publisher
- Elsevier Science
- Year
- 1981
- Tongue
- English
- Weight
- 500 KB
- Volume
- 15
- Category
- Article
- ISSN
- 0013-7944
No coin nor oath required. For personal study only.
✦ Synopsis
A new method is developed for the measurement of displacement field around cracks by using the so-called white light speckles. By spraying the specimen surface with a layer of white paint and then a layer of black paint, a fine pattern of random speckles are developed under the observation of a microscope. These speckles are photographed by double exposure before and after the application of load. The resulting specklegram is then optical--Fourier transformed to yield displacement information in terms of Young's fringes, or isothetics. A double cantilever beam is used as an example to demonstrate the technique. Displacement field and stress intensity factor around the crack tip are obtained and compared with known data.