Ballistic Resistance of ARMOX Advance according to NATO standard AEP-55 STANAG 4569

Abstract

ARMOX low-alloy high-strength steel sheet is used, among other things, as a basic homogeneous ballistic protection in plate carriers and vehicle bodies. The hardest armour plates of the ARMOX series include ARMOX Advance, which, even with a smaller thickness, provides the same ballistic protection as the stronger ARMOX 500 or ARMOX 600 sheets. The manufacturer of ARMOX armour plates declares for the ARMOX Advance with a thickness of 5 mm the resistance to small arms fire with 7.62x51 and 5.56x45 rounds according to NATO AEP-55 STANAG 4569 Annex A level 1 and for the thickness of 7 mm the ballistic resistance to small arms fire with 7.62x39 API BZ rounds according to NATO AEP-55 STANAG 4569 Annex A level 2. Due to the manufactured thicknesses, ballistic resistance is not specified for levels 3 to 6 in accordance with NATO AEP-55 STANAG 4569 Annex A. For levels 1 to 3, STANAG 4569 does not require a test against flying fragments from 155 mm artillery shells, but it is an optional component at the discretion of the national authority. In order to be able to use this type of sheet for this purpose, empirical equations were used to determine whether the conditions set out in STANAG 4569 Annex A Level 1 and Level 2 are met over the full range of ballistic resistance required. From the results obtained it was found that the ballistic resistance of ARMOX Advance armour plate against flying artillery shell fragments is not met and therefore it cannot be used alone as a basic homogeneous ballistic protection in vehicle bodies and protective sheet carriers to provide protection of persons in areas where artillery fire is expected.