• Journal of the Computational Structural Engineering Institute of Korea
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• v.32 no.3
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• pp.199-203
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• 2019

The penetration depth of a hypervelocity jet exceeding 4 km/s is described by the density ratio of the jet and the target. In the case of the same density, the difference in strength between the targets does not affect the penetration depth difference. This study focuses on the "strength irrelevance" of such a hypervelocity jet. For this purpose, the change of crater pressure caused by shaped charge jet(SCJ) was calculated by finite element analysis and the possibility of polymorphic phase transition of steel material was investigated. Hypervelocity jets were found to cause polymorphic phase transitions in the steel target craters, and the decrease in the fracture toughness of the target is predicted as the cause of the strength irrelevance.