CHARACTERIZATION AND COMPARISON OF MICROSTRUCTURES IN THE SHAPED-CHARGE REGIME - COPPER AND TANTALUM

Light microscopy, scanning electron microscopy, and transmission electron microscopy techniques were employed, along with a novel technique for building up small, recovered jet fragments using electrodeposition of copper, to examine specific segments of fabricated shaped charge liner cones and corresponding, residual jet fragments. Oxygen-free electronic copper and tantalum shaped charge regimes (liner cones and recovered jet fragments) were compared, and a reduction in the average grain size of recovered jet fragments as compared to the starting liner cones was a consistent observation. The average grain sizes for all cones was 35mum, and the maximum grain reduction occurred for an annealed, equiaxed tantalum cone, which resulted in a residual jet fragment grain size between 1 and 5mum. This is indicative of dynamic recrystallization during jet elongation and microstructure evolution.