MAGNETIC-RESONANCE IMAGES OF COARSENING INSIDE A FOAM

Coarsening in three-dimensional polycrystalline systems such as foams, magnetic bubbles, metal crystals, and ceramics is poorly understood b ecause of the absence of data describing the interior of these. materi als. We introduce magnetic resonance imaging to probe the interior of a foam, providing information on topology and foam drainage. The foam does not appear to coarsen in a self-similar way during observation pe riods of up to 50 h, representing over a decade of growth in the mean length scale.