Shock Initiation of Covered Flake JH-2 High Explosive by Simultaneous Impact of Multiple Fragments

摘要

Advances are continually being made on shock initiation of heterogeneous explosives by single fragment impact. However, most research on shock initiation of heterogeneous explosives by multiple fragment impact is still in simulation stage owing to the limitations of testing conditions and methods, and experiments on it are rare. In this study, an experiment was conducted on shock initiation of the covered flake JH-2 high explosive (HE) by simultaneous multiple fragment impact. The response level of the explosive under impact is determined by the damage degree of the cover plate and classified into detonation, explosion, deflagration and burn or no reaction. The u(2)d Held criterion was used to calculate the critical threshold I-cr of each JH-2 failure mode under the plate-sandwich charging structure. Results indicated the JH-2 HE deflagration occurs as I-cr reaches 3570.91 m(3)/s(2) by a single fragment impact, explosion occurs as I-cr reaches 6267.69 m(3)/s(2), and detonation I-cr reaches 7232.41 m(3)/s(2). Increasing the number of fragments reduces the I-cr of JH-2 HE each response level. The response level of multiple fragments impact is a multiple of single-fragment.