| Metal hydride is a potential component of energetic materials.Under the action of high temperature and high pressure of the explosion,the response characteristics of metal hydride have a significant impact on the detonation performance of composite explosives.Consequently,studying the mechanical and chemical responses of metal hydrides under high temperature and high pressure is of great significance for the development and application of metal hydride composite explosives.In this research,Zr H2,KCl O3,Zr H2/KCl O3,and Zr H2/PETN as the research object,and the detonation effect is decoupled.Firstly,the shock response of Zr H2,KCl O3,and Zr H2/KCl O3 was studied by simulating high pressure with a single-stage gas gun impact loading.According to shock recovery experiments and explosion recovery experiments,the shock reaction mechanism of zirconium hydride was explored.Afterward,the reaction characteristics and reaction mechanism of zirconium hydride in the composite explosive were studied by simulating the high temperature through electrical ignition,and the working ability of the zirconium hydride type composite explosive was evaluated by the detonation driven plate experiment.The relationship between the reaction characteristics and their working characteristics of zirconium hydride type composite explosive.The main conclusions are as follows:（1）The planar impact experiment was carried out on the porous Zr H2 with porosities of 20%and 35%by using the high-speed impact technology of the single-stage light gas gun within the pressure of 0.518～3.236GPa.The US-up relations are as follows:Us=1.879+1.639up（P=20%）,Us=0.666+2.610up（P=35%）;the shock compression characteristics of KCl O3 with P=2%were studied in the pressure of 0.840～3.924GPa.The US-up relation is Us=2.659+1.010up;the impact Hugoniot of Zr H2/KCl O3 with porosity of P=2%was studied in the pressure range of 0.252～4.903GPa,and the US-up relation was:Us=2.358+2.160up.And based on the US-up relation of each material,other forms of Hugoniot relation,including p-up,p-V,and p-ρrelations,were obtained according to the mass conservation and momentum conservation equations of plane shock waves.（2）Based on the experimental Hugoniot data of porous Zr H2 with porosity of 20%and 35%,the impact Hugoniot of Zr H2 with other porosity was predicted by using the calculation method of impact Hugoniot based on the extrapolation of pore collapse energy.The impact temperature rise curves of zirconium hydride with different porosities were calculated by the Walsh method,and it was found that Zr H2 with high porosity of zirconium hydride would obtain a higher impact temperature.（3）The high-pressure shock recovery experiments of Zr H2 were carried out by a single-stage gas gun loading,emulsion explosive contact explosion,and PETN explosive contact explosion.The recovered products were tested for particle size analysis,XRD,and SEM.The research results indicated that under the action of high pressure,Zr H2 has no obvious phase change,whereas,Zr H2 has an obvious crushing phenomenon after impact.The explosive recovery experiment of Zr H2/PETN composite explosive was carried out,and Zr O2 was found in the recovered product by XRD test.It indicates that the reaction mechanism of Zr H2 during detonation is the shock-assisted chemical reaction dominated by high temperature and supplemented by high pressure.（4）By comparing the experimental shock Hugoniot relation of KCl O3 and Zr H2/KCl O3,it is found that the addition of zirconium hydride increases the density of the composite system,which is beneficial to obtaining higher impact pressure of Zr H2/KCl O3 at the same impact speed.Meanwhile,through the impact reaction processes of KCl O3 and Zr H2/KCl O3 captured by a high-speed camera,it was found that Zr H2 as an additive could enhance the reaction activity of the composite system and prolong the reaction duration.（5）The electrical ignition experiments and detonation-driven plate experiments of Zr H2/PETN composite explosive with different Zr H2 contents and Zr H2/KCl O3 mixtures with different oxygen balances were carried out.The results indicate that the Zr H2 content and oxygen balance have significant effects on the reaction characteristics and work characteristics of the composite explosive.Zr H2 has a certain dilution effect on the energy density of explosives in the early stage.Whereas,the continuous reaction in the later stage provides functional quantities,showing an obvious afterburning effect and prolonging the continuous working time of composite explosives.The working characteristics were in good agreement with the reaction characteristics of zirconium hydride composite explosives under electric ignition. |
