关键词: 活性内芯侵爆结构, 活性材料, 断裂行为, 多层结构靶, 内爆压力

Abstract: The reactive materials filled structure exhibits unique characteristics of multiple deflagrations, layer-by-layer fracturing, and spatially distributed energy release when penetrating multi-layered plates, which relies on the fracture behavior of the penetration structure shell. To reveal the fracture mechanism of the reactive materials filled structure subjected to multiple impacts, the stress distribution model describing the shell subjected to the impact and internal deflagration loadings was developed, and the ballistic experiment of reactive materials filled structure on double-layered plates was performed. The theoretical analysis validated by the recovered fragments after the experiment indicating a novel stress reverse effect in axial stress distribution when subjected to the impact and internal deflagration loadings, which means the axial stress converts from compressive to tensile stress and shell fractures when reaches the tensile stress limit. The circumferential failure dominated by internal deflagration loading leading the cylindrical segment fractured into multiple pieces. Fracture characteristics and SEM images of fracture surfaces from different regions verify the fracture mechanism of penetration structure shell associated with the influence of two loadings: axial failure dominated by impact loading induced the reduction in penetration structure length while circumferential failure dominated by internal deflagration loading leading to the disintegration of shell. Additionally, Interior and outer area ratio S_in/S_out influences the resistance to internal deflagration loading significantly, and the initial impact velocity and internal deflagration pressure exhibit opposite effects on the fracture length.

Key words: reactive materials filled structure, reactive materials, fracture behavior, multi-layered plates, internal deflagration