Development of large-area surface detonator using an etched copper mesh and its application

A large-area surface detonator has been developed using an etched copper mesh and powder pentaerythritol tetranitrate (PETN). Five kinds of mesh patterns with zigzag bridge wires are etched from copper film sheets and the PETN powders with several particle sizes are prepared by recrystallization. The PETN charged into a shell or box with various area is initiated with electrically exploded copper mesh or parallel copper wire-rows, and the generated detonation wave has been evaluated by the arrival time jitter obtained from the streak camera record. The experimental results indicate that the flatter detonation front is generated in PETN with finer particle size, and the explosion of the selected mesh pattern has initiated the PETN surface simultaneously, almost the same as that of the wire-rows. Moreover, the mesh explosion technique has been applied to initiate a cylindrical PETN shell. The experimental results indicate that the mesh initiation technology is applicable to produce one-dimensional cylindrical imploding detonation by simultaneous surface initiation of cylindrical PETN shell with an axial length long enough. Finally, a flyer acceleration system has been examined. It becomes known that the PETN detonation initiated with the mesh explosion can accelerate a polyethylene terephthalate (PET) flyer up to 2.8 km/s.