Response And Load Transfer Characteristics Of PBX Explosive Substitution Materials Under Impact Load

PBX(Polymer bonded explosive)is the abbreviation of a class of polymer bonded explosives,which are composed of energetic particles and binders,and is used in weapon warheads and large-scale destructive weapons.In this paper,PBX explosive substitute material(PBS)was prepared considering the safety of the shelled charge test by using white sugar,plasticized hydroxy-terminated polybutadiene(HTPB),dioctyl maleate(DOS)and toluene disocyanate(TDI).First,stress-strain curves of PBS at different strain rates were determined using a Hopkinson pressure bar.The results showed that the strain rate effects of PBS were obvious.The morphology of the microscopic lesions of the PBS before and after loading was observed under the scanning electron microscope(SEM).It was found that the mesostructure and damage morphology of the PBS are consistent with the PBX and that the main damage mechanisms include debonding and particle cracking.Using Maxwell's generalized viscoelastic model,the dynamic constitutive model of PBS was created,the correctness of which was confirmed by experimental results.Secondly,the dynamic mechanical response of the PBS under planar shock loading conditions was investigated by using the"symmetric collision"approach to obtain the sound velocity C₀ and the shock factor?.The Grüneisen equation of state parameters of the PBS were obtained by combining the planar positive shock wave theory.Then,the load transfer experiment in the shelled PBS was carried out,and the load amplitudes at different positions of the PBS charge were obtained.Using the quasi-one-dimensional plane shock wave hypothesis,the internal response law of the shelled charge under the shock load was analyzed,and the load transfer model in the shelled PBS was constructed.Finally,the viscoelastic components and equations of state defined above were substituted into the numerical model,and the numerical simulation study of the load transfer experiment of the PBS and PBX shelled charge was carried out.The numerical simulation results of the two materials were basically consistent,verifying the viscoelastic constitutive,the PBS equation of state and the numerical simulation process are correct.The results of numerical simulation of PBS basically coincide with the corresponding experimental curves,which confirms the correctness of the experimental results.