Interval rupturing damage to multi-spaced aluminum plates impacted by reactive materials filled projectile

A series of experiments are performed to investigate the damage effect of multi-spaced metal plates impacted by the reactive materials filled projectile (RMFP) at a velocity about 1100 m s ^{− 1}. The RMFP is a structural penetrator by replacing projectile's usually inert core with reactive material. The multi-spaced metal plates consist of a front steel plate followed by five aluminum plates. The front steel plates used have thicknesses of 10, 20, and 30 mm. All five spaced aluminum plates are 3 mm thick with the same spaced distance of 300 mm. The distance between the front steel plate and the first aluminum plate is 600 mm. The experimental results indicate an unusual interval rupturing damage phenomenon in the multi-spaced aluminum plates, revealing a strong dependence upon the thickness of the front steel plate: with increasing the thickness of the front steel plate from 10 mm to 30 mm, the damage to the first aluminum plate increases but the interval rupturing damage to the multi-spaced aluminum plates structure decreases significantly. Furthermore, to understand this unusual damage behavior, an analytical model is developed, by which the front steel plate's thickness effect on the interval rupturing damage to the multi-spaced aluminum plates is discussed. The model analysis shows that, with increasing the thickness of the front steel plate, the initiated reactive material filling length increases, resulting in a higher deflagration overpressure in the filling, greater radial expansion effects of the jacket, and shorter projectile remainder, thereby enhancing the rupturing damage to the aluminum plates near the front steel plate but reducing the rupturing damage to the other aluminum plates.