Research On The Damage Characteristics Of Explosives In Vehicle-mounted PBX Under Explosive Shock Environmen

Energetic materials such as vehicle mounted PBX explosive will produce certain damage when subjected to explosion impact load,reduce the reliability and expected power of energetic materials,and even cause accidental explosion of energetic materials after impact.In order to ensure the reliability and safety of energetic materials as explosion energy source and structural materials and improve the understanding of the law of damage response to performance,the main contents of this paper are as follows:(1)Referring to the literature,the typical impact load that can cause damage to energetic materials and affect their performance is determined as the fragment impact produced by explosion.The fluid structure coupling simulation is carried out by using Lagrange algorithm and ALE algorithm to determine the impact velocity of high-speed fragments produced by explosion;(2)Based on the impact velocity of high-speed fragments,the loading condition is determined as high strain rate condition.The high strain rate constitutive relation acquisition test of PBX explosive material,namely split Hopkinson pressure bar(SHPB)test,was carried out to obtain its high strain rate mechanical properties.Various details of the test were explored and controlled,and the constitutive relation of damage of PBX explosive material in the strain rate range of 1300 / S ～ 6100 / s was obtained;(3)Based on the constitutive relationship obtained from the experiment,an appropriate model is selected to mathematically characterize the constitutive relationship.Using the material subroutine interface of commercial finite element software,the writing method of material subroutine is studied from the aspects of programming syntax and calculation logic,and the writing and verification of material subroutine are completed;(4)The verified material subroutine is used to simulate the impact of explosive fragments with shell,which can display the cloud diagram of stress,strain and damage variables.Through the results,the stress characteristics and damage evolution law of PBX explosive materials under the impact load that may be suffered in the vehicle environment are analyzed,which provides a simulation tool for the performance research of energetic materials in complex environment.