A FEM Analysis Of Thermodynamic Effect Of Materials Irradiated By Pulsed X-ray

When the X-ray irradiats the materials,the photons have a complex mutual process with the atoms and electrons of the materials. Finally the energy of the X-ray transform into the internal energy of the target.During this process,Firstly the front area ablates,and next,the vaporizaton expand freely which leads to a pulsed pressure to the rest part of the materials.Simultaneously,the front area has a restricted thermal dilation.The two process mentioned above lead to a compressive stress into the target.The stress wave reflection occurs at the back free surface,the tensile wave transmit reversely.This may induce a spall fracture.In this paper, Based on the Tshock2 D programme which is coded in Fortran90 language,We re-programmed to simulate the Flyer impact and X-ray irradiation to the target of aluminium and carbon-bakelite plane and Focus on the thermodynamics damage of these materials loaded by X-ray irradiation.The result of the simulation shows that:(1)In caculating the ablation of the target,if the X-ray is hard then liquefaction has a domination than the effect of vaporization near the surface.(2) If the heat inteneration is considered in the constitutive equation,the pressure of the shock wave shall fall and it has a great influence on the hard X-ray than the soft one.(3) To simulate the liquefaction ares, Grover model is established to caculate the pressure.The result shows that the peak stress fall.During the process,the hard X-ray affected the stress more than the soft X-ray.(4) In order to study the thermodynamic response of the phenolic polymer matrix composite material,A modified Murnaghan EOS is established.(5) we make a comparision in fracture of materials between maximum tensile stress criteria and damage accumulation criteria and the latter has a better performance with the experimental data.(6) The comparison of impulse coupling coefficient in various energy flux shows that soft X-ray has a larger impulse coupling coefficient than the hard one.But the efficient decrease with the increasing of energy flux,and the hard X-ray has an opposite conclusion.