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Formation behaviors of rod-like reactive shaped charge penetrator (RRSCP) and their effects on damage capability are investigated by experiments and numerical simulations. The pulsed X-ray technology and a spaced aluminum/steel plate with the thicknesses of 5 mm/100 mm are used. Three types of spherical-segment aluminum-polytetrafluoroethylene-copper (Al-PTFE-Cu) reactive liners with Cu contents of 0%, 46.6%, and 66% are fabricated and tested. The experimental results show that the reactive liners can form excellent rod-shaped penetrators with tail skirts under the shaped charge effect, but the tail skirts disappear over time. Moreover, rupturing damage to the aluminum plate and penetration to the steel plate are caused by the RRSCP impact. From simulation analysis, the RRSCP is formed by a mechanically and chemically coupled response with the reactive liner activated by shock in its outer walls and bottom and then backward overturning, forming a leading reactive penetrator and a following chemical energy cluster. The unique formation structure determines the damage modes of the aluminum plate and the steel plate. Further analysis indicates that the formation behaviors and damage capability of Al-PTFE-Cu RRSCP strongly depend on Cu content. With increasing Cu content, the velocity, activation extent, and reaction extent of Al-PTFE-Cu RRSCP decrease, which contribute to elongation and alleviate the negative effects of chemical reactions on elongation, significantly increasing the length-diameter ratio and thus enhancing the capability of steel plate penetration. However, the lower activation extent and energetic density will weaken the RRSCP's capability of causing rupturing damage to the aluminum plate.

To investigate the thermal response and initiation behavior of ternary fluoropolymer-matrix PTFE/Al/W reactive materials, a research combining shock loading tests and trans-scale modelling is conducted. On the basis of a good agreement of the numerically simulated and tested shock wave propagation, the significant impact of component ratios and particle sizes on the evolution of mesoscopic temperature, hot-spots and initiation is well characterized and analyzed. Results demonstrate that as the content of W increases, the range of mesoscopic high-temperature area increases and tends to distribute more uniform, while material with smaller W particles causes more intense particle deformation and larger temperature rise. The time to reach the critical temperature shows positive correlation to the content of W, while the critical temperature of hot-spots shows negative correlation to the particle size of W. For PTFE/Al/W of high density, with the increase of W particle size, the reaction rate decrease, however the time to reach the peak reaction rate shortens.

A series of ballistic experiments were performed to investigate the damage behavior of high velocity reactive material projectiles (RMPs) impacting liquid-filled tanks, and the corresponding hydrodynamic ram (HRAM) was studied in detail. PTFE/Al/W RMPs with steel-like and aluminum-like densities were prepared by a pressing/sintering process. The projectiles impacted a liquid-filled steel tank with front aluminum panel at approximately 1250 m/s. The corresponding cavity evolution characteristics and HRAM pressure were recorded by high-speed camera and pressure acquisition system, and further compared to those of steel and aluminum projectiles. Significantly different from the conical cavity formed by the inert metal projectile, the cavity formed by the RMP appeared as an ellipsoid with a conical front. The RMPs were demonstrated to enhance the radial growth velocity of cavity, the global HRAM pressure amplitude and the front panel damage, indicating the enhanced HRAM and structural damage behavior. Furthermore, combining the impact-induced fragmentation and deflagration characteristics, the cavity evolution of RMPs under the combined effect of kinetic energy impact and chemical energy release was analyzed. The mechanism of enhanced HRAM pressure induced by the RMPs was further revealed based on the theoretical model of the initial impact wave and the impulse analysis. Finally, the linear correlation between the deformation-thickness ratio and the non-dimensional impulse for the front panel was obtained and analyzed. It was determined that the enhanced near-field impulse induced by the RMPs was the dominant reason for the enhanced structural damage behavior.

The compression behavior of polytetrafluoroethylene (PTFE)-aluminum (Al) is studied by the means of the two-dimensional finite element analysis of mesoscale model containing a random dispersion of particles. The results show that for composite materials with a single particle size the strength of the material increases first and then decreases with the increase of the content of metal particles. When the particle content is high the strength of the material can be improved by a reasonable particle gradation. The influence of particle content and size on the strength of particle composites is obtained and theoretical analysis is carried out from the perspective of the formation and evolution of force chains.