Instability of a Conical Liner during Shaped-Charge Jet Formation

Abstract

Instability of a conical liner during shaped-charge jet formation has been studied. To establish the metal flow pattern during shaped-charge jet formation, we fabricated three-layer copper-copper-Constantan liners consisting of a solid copper conical cone with a cone angle of 45°, a wall thickness 1.5 mm, and a cone pressed into it and rolled from a copper sheet 1.0 mm thick clad on the inside with Constantan 0.2 mm thick by explosive welding. Liner compression was carried out by an RDX charge 20 mm thick. The jet formation process was recorded by flash radiography, and the metal flow pattern was determined by micro sections of recovered slugs. Since the interface between the explosively welded metals is clearly distinguishable in the sections, the residual deformation in different sections of the slug shows the occurrence of liner instability during the compression, which manifested itself as folds oriented along the generatrix of the cone. At the same time, the general flow pattern described in terms of the theory of an ideal incompressible fluid is not disturbed, which follows from radiographs of the shaped-charge jet formation process.