Hypervelocity jet interaction with lightweight flyer plates

Deniz, Tansel
Explosive Reactive Armor (ERA) is an efficient way of defeating threats with shaped charge warheads. It comprises an explosive layer between two steel plates. In the typical arrangement, cassettes are placed in obliquity to the flight path of the jet. Shaped charge jet detonates the explosive layer and flyer plates are accelerated in opposite directions. The mechanism of the plates is to deflect or disrupt the jet. On the other hand, the plates may damage the structure of the vehicle. Moreover, the plates flying in the outer direction may possess a threat to nearby personnel or vehicles. To overcome this shortcoming, it is plausible to propose cassettes with brittle or low-density materials. This thesis aims to investigate the potential of ceramics and glass as flyer plate materials. First, the ballistic protection performance of steel-steel cassettes with varying plate and explosive layer thickness is examined. Then, for a given areal density, the front and back plates of the cassette are changed selectively with alternative materials, and the ballistic performance is tested. The materials that reveal the best performance as front and back plates are selected. Finally, the performance of non-steel cassettes with selected materials is investigated. Hydrocode numerical modeling is performed to understand the nature of the interaction between jet and flyer plates. It is seen that ceramics can be used as a replacement for steel in ERA, achieving similar or even better efficiency. It is also revealed that the performance of ceramic flyer plates depends on compressive strength, fracture toughness, and bulk impedance.


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Citation Formats
T. Deniz, “Hypervelocity jet interaction with lightweight flyer plates,” Ph.D. - Doctoral Program, Middle East Technical University, 2022.