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Quasi-static tension tests, quasi-static compression tests and dynamic compression tests were conducted to investigate the mechanical properties, constitutive behaviors and failure criteria of aluminum-polytetrafluoroethylene-tungsten (Al-PTFE-W) reactive materials with W content from 20% to 80%. The analysis of the quasi-static test results indicated that the strength of the materials may be independent of the stress state and W content. However, the compression plasticity of the materials is significantly superior to its tension plasticity. W content has no obvious influence on the compression plasticity, while tension plasticity is extremely sensitive to W content. Dynamic compression test results demonstrated the strain rate strengthening effect and the thermal softening effect of the materials, yet the dynamic compression strengths and the strain rate sensitivities of the materials with different W content show no obvious difference. Based on the experimental results and numerical iteration, the Johnson–Cook constitutive (A, B, n, C and m) and failure parameters (D1~D5) were well determined. The research results will be useful for the numerical studies, design and application of reactive materials. [ABSTRACT FROM AUTHOR]

Polytetrafluoroethylene/aluminum (PTFE/Al) reactive material is a pivotal research object in the aerospace, military, and mechanical engineering fields and can release chemical energy (CE) under shock or impact. However, its relatively low mechanical strength limits its applications. The present paper proposes a Cu-PTFE/Al (73.5wt. %/26.5wt. %) double-layer liner that can form tandem explosive formed projectiles (EFPs) under the shock of shaped charges, which not only retains the strong penetration ability but also shows a more significant lateral enhancement effect through the deflagration reaction. Here, the preparation process of the PTFE/Al liner is given, and an analytical model for the Cu-PTFE/Al tandem EFP of the damage process against multi-spaced plates is established, revealing the penetration and deflagration-enhanced mechanisms. Subsequently, a two-step segmented numerical simulation for the penetration–deflagration coupling effects is conducted, and the time-space interaction process and damage results between kinetic energy penetration and CE deflagration are obtained. A series of experiments of tandem EFPs against spaced plates are conducted, including the different materials, thickness ratio, and standoff. Experimental results show that compared with Cu–Cu tandem EFP with the same condition, the penetration ability of Cu-PTFE/Al composite EFP is reduced, but the damage enhancement effect is greatly improved; the maximum damage area of a single plate is increased by 220.1%, and the average damage area of a single plate is increased by 76.2%. This study provides important reference data and a theoretical basis for the design of metal-reactive tandem EFPs. [ABSTRACT FROM AUTHOR]