Publications

Effect of microstructure on the detonation behavior of vapor-deposited pentaerythritol tetranitrate (PETN) films

Knepper, Robert; Forrest, Eric C.; Marquez, Michael P.; Tappan, Alexander S.

The microstructure of pentaerythritol tetranitrate (PETN) films fabricated by physical vapor deposition can be altered substantially by changing the surface energy of the substrate on which they are deposited. High substrate surface energies lead to higher density, strongly textured films, while low substrate surface energies lead to lower density, more randomly oriented films. We take advantage of this behavior to create aluminum-confined PETN films with different microstructures depending on whether a vapor-deposited aluminum layer is exposed to atmosphere prior to PETN deposition. Detonation velocities are measured as a function of both PETN and aluminum thickness at near-failure conditions to elucidate the effects of microstructure on detonation behavior. The differences in microstructure produce distinct changes in detonation velocity but do not have a significant effect on failure geometry when confinement thicknesses are above the minimum effectively infinite condition.