Techniques for Flaw Detection in Composite Material Structures.

摘要

This study concerns the nondestructive detection and quantification of flaws and voids in thin, cylindrical, fiber reinforced, composite, structures. Three types of flaws were investigated using shearing speckle and single beam speckle interferometry. The theory for each technique and photographs of the fringe patterns are presented. The Young's fringe method of speckle interferometry was used to determine the surface strains in the flaw region and the resulting flaw geometry was presented in graphical form. Shearing speckle interferometry was developed for a qualitative analysis only. The results show that flaws in their fiber reinforced composite structures can be detected and the size determined by either shearing speckle or single beam speckle interferometry. (Author)