Parameter determining the concentration of crystal structure defects in shock-compressed copper

Experiments on measuring the electrical resistance of copper foil under shock compression are analyzed for determining the basic parameters responsible for the concentration of shock-induced defects in the metal. Based on the excessive electrical conductivity of the metal, the concentration of point defects of the crystal structure in copper samples placed in various cartridges (Plexiglas, micarta, and fluoroplastic) is estimated. The cartridge material is found to affect the number of defects arising due to shock compression of the metal. The cartridge with a higher shock impedance corresponds to a smaller concentration of defects in the sample (at identical pressures of the shock wave in the cartridge). A physical model of generation of crystal structure defects due to shock compression is formulated to explain the experimental results obtained. According to this model, defects are formed during matter compression in the shock wave front and remain “frozen” after unloading. A new portion of defects is formed after secondary compression of matter, resulting in accumulation of defects. It is assumed that the parameter determining the number of defects arising under dynamic loading is the algebraic sum of metal deformations at each stage of shock compression. The data presented in the variables concentration of defects - deformation yield a dependence that mitigates the difference in the cartridge material. The analysis performed shows that the sum of deformations can be considered as a parameter determining the concentration of defects generated by shock compression of copper.