Papers by Author: Rolf Prümmer

Abstract: Widely known technologies of explosive (X) welding and explosive (X) powder compaction are based on applications of porous composite solid or liquid explosives. Recent results on dynamics of X-welding and X-powder compaction are presented and discussed in this paper in the conceptual context of an orderly oscillating detonation wave (DW), a synergetic phenomena observed in detonation of all classes of composite energetic materials, that was discovered in LEDAP in last eight years. Regular instabilities that are induced by oscillating DW, are transmitted through the interface of the impacted materials, causing the local instability and fluctuations in both processes, formation of the interfacial waves (X-welding mechanism) and in an initial phase of powder compaction. Application of high resolution optical probes (spatial resolution 250 *m, temporal resolution 1 ns, 96 independent channels) allowed the simultaneous registration of the oscillating DW in the X-charge and transmission of oscillations, trough the flyer plate, up to the welding zone. Similar measurements have been made in experiments with X-compaction of tungsten powder providing the continuous registration of shock wave velocity inside the compacted powder, its geometrical shape, their instabilities and irregularities.

Abstract: Hot isostatic pressing (HIP) is the established procedure to process Udimet 700 Powder by Powder Metallurgy (P/M) techniques. In this paper the method of hot explosive pressing (HEP) was applied. Its main feature is the direct method of explosive pressing. To avoid any reaction beforehand, the heating device and the explosive compaction device are separated and brought together very rapidly just a few milliseconds before ignition of the explosive charge. Udimet 700 bulk samples are obtained and investigated by metallographic and mechanical testing.