Holographic Techniques for Defect Detection in Composite Materials

The results of an experimental study of holographic interferometry and tetrabromoethane (TBE)-enhanced X-ray photography for damage detection in composite materials are presented. The results show that holographic interferometry using thermal loading can accurately track delamination growth, but cannot find subsurface matrix cracks. It can also provide information on the through-the-thickness distribution of delaminations. TBE-enhanced X-ray photography can find matrix cracks, delaminations, and fiver bundle fractures, but gives no information on the through-the-thickness distribution of the damage.