When the detonation reaction occurs after the charge in the warhead is ignited, the propagation of the detonation wave and the expansion of the detonation product will interact with the wrapped metallic shell and cause the shell material to accelerate, extremely deform, and eventually rupture, which is a typical strong fluid-structure interaction problem. In this paper, a comparison investigation on a cylinder test in different ambient media was implemented by experiment and numerical simulation, respectively. In the experimental test, the attention was paid to discussing the differences of the accelerating process of the cylinder metal wall, the expansion modes, and the fragment shape of the cylinder due to the medium with different shock wave impedance which surrounds the cylinder shell. For the numerical simulation, a coupling scheme of a meshless method and finite element method called the coupled finite element material point method was used to reproduce the cylinder expansion problem driven by explosive sliding detonation where the interaction between the cylinder wall and the explosive/detonation product is enforced by using a point-to-surface contact scheme to accurately achieve contact and separation between material particles and finite elements. Lastly, the macroscopic and microscopic states of the cylinder failure were compared and discussed for further discussion.

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Reactive materials (RMs) are usually prepared from metal/non-metal mixed powders through hot processing. The main feature of the material is that it will react and release energy when impacted. However, the impact-induced chemical energy release during impact has a complicated mechanism and needs to be further explored. This work investigated the impact-induced chemical process by split Hopkinson pressure bar and low-pressure experimental system, different atmospheric pressure environment has been simulated. Moreover, High-speed photography was used to reveal the macroscopic ignition phenomena. Furthermore, X-ray diffraction (XRD) was used to study the material composition of raw and recovered specimens. The results of the experiments described here clearly show that metal reacts with oxygen and PTFE at atmospheric environment, which reaction produces are metal oxides and metal-fluoropolymers. However, the material only undergoes fluorination reaction at low pressure, which reaction produces only has metal-fluoropolymers. Meanwhile, the reactive ratio of the material increases with the pressure increase, furthermore, the maximum reaction ratio of the material in an atmospheric pressure environment is about 29.5 %, which reaction ratio is 4.7 times more than the pressure of 750 Pa.