Three dimensional microstructure of polymeric composite materials used in sandwich structures using dual modality from combined high resolution X-ray and neutron tomography

Use of dual modality to study polymeric composite materials with high resolution X-ray and neutron tomography is demonstrated for the first time in this study. X-ray and neutron tomography techniques provide an ability to visualize and quantitatively describe the microstructure in three dimensions (3- D) non-invasively. 3-D image based registration is performed to combine the two modalities that account for varied resolutions and contrast. Authors are studying the effect of degradation of carbon fiber vinyl ester based composites due to sea water exposure and the damage diagnostic techniques from tomography, and are finding beneficial use to understand the complex coupling of microstructuremechanical property relationships. Quantitative information such as local versus global variation of fiber and resin volume fraction, analysis of voids or cracks, and anisotropy of attenuation properties are being evaluated in 3-D for use in studying these complex materials used for marine ship sandwich structures.