Experimental and Numerical Investigation of Bodywork Effect on High-Hardness Armour Steel Against a 7.62 x 51 mm NATO Ball M80 Projectile

Small arms ammunition like the 5.56x45 mm NATO Ball and 7.62x51 mm NATO Ball projectiles constitute a significant threat to light armoured vehicles. These vehicles are mostly comprised of single-layered metallic highhardness steel armour, but as an essential vehicle design feature, mild steel bodywork is externally mounted in certain areas for fenders, toolkit boxes, storage boxes, etc. over the main armour, i.e., high-hardness steel armour. These are necessary design features of vehicles, so they can't be neglected regarding ballistic protection against threats. Also, to provide better ballistic protection in up-armoured vehicles, armour consisting of high-hardness steel armour is integrated or mounted just behind the existing bodywork of the car. Thus, this paper experimentally and numerically investigated the "bodywork effect," which is also called the "K-effect," and found that the configuration where the bodywork of mild steel is placed in front of high-hardness steel armour plate failed to provide better ballistic protection against the 7.62x51 NATO Ball M80 projectile fired at 0 degrees angle of impact with a velocity of 833 +/- 20m/s from 10 m distance. However, the single high-hardness armour steel plate provided better ballistic protection than the configuration consisting of bodywork. For the validation of the experimental investigations, the arrangements were numerically simulated. The main aim of this work was to check the bodywork effect against this particular projectile and investigate factors contributing to the phenomenon.