Mechanism of high-velocity blunt-nosed projectiles penetrating moderately thick UHMWPE fiber reinforced plastic laminate

According to different mechanical states and energy-dissipative mechanisms during penetration process, together with the high-velocity penetration-resistant characteristic of ultra-high molecular weight polyethylene fiber reinforced plastics (UFRP), the whole process of high-velocity blunt-nosed projectiles penetrating moderately thick UFRP is divided into three consecutive phases, i.e., compression & mushrooming phase, shearing & compression phase and stretching deformation phase. Based on three-phase penetration mechanism, an analytical model was developed to compute ballistic limits and residual velocities of projectiles penetrating moderately thick UFRP. Ballistic limits and residual velocities of projectiles for different test cases in a correlative reference were calculated by the model. Good agreements are obtained between the calculated values and experimental results. The three-phase penetration model, which considers the phenomenons of melted fibers due to frictions and mushrooming of projectiles existing in ballistic tests, can be employed to reasonably predict ballistic limits and residual velocities of high-velocity blunt-nosed projectiles penetrating moderately thick UFRP. The model has theoretical and engineering application values.