Region distribution of PTFE/Al-Ti composite jet and its penetration-deflagration damage mechanism for multi-spaced targets

The reactive material-metal composite jet has received increasing attention due to the dual penetration-deflagration enhancement effect from high penetration of metal and deflagration reaction of Al and polytetrafluoretyhylene (PTFE) in the practical applications. In order to obtain the corresponding damage behavior and the mechanism of PTFE/Al-Ti composite liner shaped charge against multi-spaced plates, four types of multi-spaced targets with the Al plate spacing of 50, 100, 150 and 200 mm were performed to investigate the damage effect. The experimental results show that the PTFE/Al-Ti composite jet could cause significant chain damage to the multi-spaced targets, which was more severe than that of the conventional Ti jet. Moreover, the damage effect of the Al plate with the same number was weakened as the plate spacing increased from 50 to 200 mm, and the initiation delay reaction characteristic was found to be the dominant factor. To further understand the corresponding damage mechanism, a numerical model was developed to simulate the penetration process of PTFE/Al-Ti composite jet against multi-spaced targets based on the AUTODYN-3D code. A penetration-deflagration damage mechanism derived from the chain collaboration of the precursor Ti jet penetration and PTFE/Al materials deflagration. Thus, the mass distribution of the initiated PTFE/Al materials between spaced targets was the key factor influencing the chain damage effect, only the perforated plates within the deflagration damage region presented a burst damage pattern. This work offers an effective way to design composite jet and enhanced damage effect for the practical application.