Study on the reactive material filled structure under impact loading: Progressive perforation on spaced plates

The reactive materials filled structure (RMFS) exhibits self-distributed energy release when impacting spaced plates, causing a progressive perforation damage effect on the plates. This research employs both experimental and analytical approaches to investigate the damage effect of the spaced plates when subjected to multiple impacts from RMFS. Detonation-like cutting (DLC) and deflagration-induced tearing (DIT) damage modes are identified based on the morphologies of damaged plates. Experimental results suggest that increasing the initial impact velocity from 594 m/s to 819 m/s promotes a transition of the plate damage mode from kinetically dominated DLC to deflagration-driven DIT. Meanwhile, the total damaged area increases from 3585.4 cm² to 8811.8 cm², with the location of the maximum damage area shifting from the third to the fourth plate. A two-stage plate petalling model considering the coupled impact and deflagration loadings is developed and validated against experiments by deformation parameters, along with the spatial mass and velocity distributions model of RMFS, the progressive perforation mechanism of spaced plates is revealed. By increasing the initial impact velocity, the mass and reaction degree of the initiated RMs filling at each impact are enhanced, thereby changing the spatial energy distribution properties of RMFS, characterized by E_def, E_K, E_def/E_K, and E_K+ΣE_def. Such self-distributed energy release behavior of RMFS during penetrating spaced plates agrees well with the observed variation in the damaged area of the plates. Additionally, the underlying mechanism of transition from DLC to DIT damage modes under multiple impacts is discussed respectively.