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RESEARCH ON DISTRIBUTION OF BEHIND-ARMOR DEBRIS FROM PENETRATION OF TARGET BY EFP WITH DIFFERENT LENGTH-DIAMETER RATIO

To research the distribution of behind-armor debris (BAD) of explosively formed penetrator (EFP) more comprehensively, three EFPs with different length-diameter ratio (L/D) were designed, and experimental study on the dispersion characteristics of BAD from EFP penetrating 45# steel target was carried out. The morphology and scattering characteristics of debris cloud after EFP penetrating steel target were observed by X-ray photography and high-speed photography, and BAD were recovered by the method of stacking fiber plates and polystyrene plates. The mass spatial distribution law of projectile material and target material fragments was obtained. Results indicate that the increase in EFP L/D has a greater increase on the normalized axial expansion velocity of debris cloud than the radial expansion velocity. The average mass and perforation area of fragment corresponding to the relative accumulation value of 1/2 both decrease with the increase of the EFP L/D. The increase of EFP L/D mainly enhances the concentration of the EFP fragment mass towards the residual penetrator axis, but has little effect on the target fragment mass, which is basically uniformly distributed along the scattering angle.