Experimental and numerical study of the ballistic performance of steel fibre-reinforced explosively welded targets impacted by a spherical fragment

Steel fibres were used to reinforce the layered targets with surface-to-surface combination. The two- and three-layer metal targets with a total thickness of 5 mm were fabricated by explosive welding. The damage mechanism and the anti-penetration performance of the targets were studied experimentally and numerically using the LS-DYNA 3D finite element code. The effects of layer number and fibre spacing density on the anti-penetration performance were discussed. The results show that the failure modes of the steel front plate were shearing and plugging, and that the failure mode of the aluminium rear plate was ductile prolonging deformation when the tied interface failed by tension (or shearing and plugging when the interface remained connected) for the two-layer target. For the three-layer target, the failure modes of the steel front plate and the aluminium middle plate were shearing and plugging, while the steel rear plate failed by ductile prolonging deformation. At the same time, the steel-fibres failed by bending and tensile deformation. The anti-penetration performance of the three-layer composite targets was better compared with the performance of the two-layer targets when the areal density and fibre spacing density were equal. The reinforced fibres will improve the anti-penetration performance of the targets, and the ballistic resistance decreased with an increase in the fibre spacing distance.