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Eroding Penetrators

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Terminal Ballistics

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Abstract

This chapter deals with the penetration process of eroding penetrators, namely, long rods and shaped charge jets. The subject is of much interest for both warhead designers, who try to improve the penetration capabilities of these threats, and for armor engineers who try to defeat them with lighter and cheaper designs. As described in Chap. 1, a shaped charge jet is formed by the collapse of a thin walled conical liner, usually made of copper, which is inserted in a conical cavity at the end of a cylindrical explosive charge. Following the detonation of the explosive the copper liner is collapsing on itself, forming a long and thin jet, a few millimeters in diameter, which moves at extremely high velocities. In fact, the jet elements acquire different velocities during the collapse, and they move at a continuous velocity gradient from tip to tail. The head of the jet can reach velocities in excess of 8 km/s, while its tail is moving at about 3 km/s. A slower and much thicker part of the jet, called slug, is trailing behind at a velocity of about 2.0 km/s. Due to this velocity gradient, the jet can reach lengths of the order of 1 m, resulting in similar penetrations depths armor steels. Long rod penetrators have aspect ratios in the range of L/D = 20–30 and diameters of about D = 20 mm. These rods are made of high density materials such as tungsten heavy alloys (WHA) or depleted uranium (DU), with densities of 17.0–18.0 g/cm3. Long rods can penetrate armor steel targets of thicknesses which are equal to their lengths, at impact velocities in the range of 1.5–1.7 km/s.

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Authors and Affiliations

  1. Ballistics Center, RAFAEL, Haifa, Israel

    Zvi Rosenberg & Erez Dekel

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  1. Zvi Rosenberg
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  2. Erez Dekel
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Correspondence to Zvi Rosenberg .

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Rosenberg, Z., Dekel, E. (2012). Eroding Penetrators. In: Terminal Ballistics. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-25305-8_5

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  • DOI: https://doi.org/10.1007/978-3-642-25305-8_5

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