论文信息 - NONDESTRUCTIVE DETECTION OF SIMULATED DELAMINATIONS IN COMPOSITE LAMINATES BY LASER‐SPECKLE SHEAROGRAPHY

NONDESTRUCTIVE DETECTION OF SIMULATED DELAMINATIONS IN COMPOSITE LAMINATES BY LASER‐SPECKLE SHEAROGRAPHY

The application of laser-speckle shearography to nondestructive evaluation of composite structures is examined. The shearography method, developed by Hung et al., consists of two optical arrangements. The first, the construction arrangement, develops the shearogram, and the second optical arrangement, the reconstruction arrangement, is utilized to process the optical information of the shearogram. The effectiveness of this optical system is evaluated by comparing experimentally derived out-of-plane displacement-gradient contours of a centrally loaded clamped disk with theoretical values; good agreement between the data is observed. An example in which the shearographic system is used to investigate delaminations in a graphite/epoxy, ten-layer, crossply, laminated plate is presented. Diagrams of the shearographic system are provided. 14 references.

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