07 May 1993
Vol 260, Issue 5109

About The Cover

Spatial orientation and interconnectedness of porosity in a silicon carbide composite reconstructed from data produced by high-resolution x-ray tomography. Such imaging can measure surface area changes during chemical vapor infiltration, allowing validation of models of the composite microstructure. See page 789. [Image: Thomas Breunig and John Daniel, Sandia National Laboratories]