Study On Mechanical Properties Of Al/Ni Active Materials After Explosive Loading

Traditional weapons are limited by the kinetic energy damage efficiency,and cannot meet the complex needs of modern battles.Reactive materials come into being in order to increase the power of the warhead.It not only has the traditional kinetic energy damage effect,but also the chemical damage effect such as explosion and combustion,which greatly improve the comprehensive damage ability.Reactive materials will be driven by strong detonation when applied to warhead fragments or charge shields,so their mechanical behavior and energy release characteristics will be affected to a certain extent.Explosive impact loading causes the state of the active material to change,and if the performance of the initial state of the material is used to guide the warhead design and damage effectiveness evaluation,the design damage effectiveness will not match the actual damage effectiveness.In this paper,typical Al/Ni reactive material was taken as the research object,considering the particle size and explosive impact strength.Dynamic and static compression tests and quasi-closed container tests were performed on the explosive recovery material and the comparative material,so as to study the dynamic and static mechanical behavior and failure behavior of the Al/Ni material after explosive impact loading.It will be an excellent guide for establishing the complete working process of reactive material,perfecting the impact initiation model and designing the warhead.In this paper,a quasi-closed container shock reaction test was carried out on the material loaded by detonation.The explosive shock reduces the energy release efficiency of the material.The greater the intensity of the explosive shock,the greater the reduction ratio: compared with the material without detonation load,loaded with 14.76 GPa,21.79 GPa and 28.84 GPa,the reactivity decreased by 26.6%,78.8% and 80.5%,respectively.A dynamic and static mechanical test was carried out,considering the particle size factor to study the mechanical behavior and failure behavior of the active material.The test shows that the smaller the particle size,the greater the explosive impact strength of the active material has better mechanical strength.Due to the incompatibility between the elastic modulus of the aluminum-nickel particles and the melting point,the nickel particles move and aggregate in the aluminum matrix after being loaded,and pores appear at the particle boundaries,and gradually expand into cracks.The elasto-viscoplastic dynamic constitutive model of Al/Ni material was established which describes the mechanical property of the material.The impact of explosion effect weakly on the elastic stage of the material,but affects the viscoplastic stage.It means that the original material parameters cannot be used to judge the working conditions of reactive material,and the explosion conditions of loading need to be additionally considered.