ИСТИНА

The results of experimental and theoretical studies of the effect of nanosize inert additives on the threshold voltage of initiation of explosive reactions in high energy materials (HEM) are presented. Two HEMs were studied: (i) based on potassium picrate and (ii) based on the red lead. The particle size for both HEMs was ~ 100 μm. As nanosize additives, we used: (i) copper nanopowder with particle sizes of 100-130 nm and (ii) detonation nanodiamonds with particle sizes of less than 100 nm. It was found that (i) the electric breakdown of the powder composition is the primary phenomenon, while the initiation of HEM is a consequence of this breakdown; (ii) when adding the nanosize additives to the HEMs, a significant decrease in the initiation voltage is observed; herewith the larger the content of the nanosize additive the more decrease in the initiation voltage; (iii) the higher the rate of voltage rise in the experiment, the greater the breakdown voltage of HEM with nanosize additives. A model of electric breakdown of HEM with nanosize additives is suggested. It is shown that the dependence of the breakdown voltage on the content of nanoadditive is connected with the inertness of formation of percolation clusters of nanoparticles in the electrostatic field and with a finite rate of voltage rise. Criterial dependencies describing the change in the breakdown voltage on the content of the nanosize additive in the sample are obtained. The obtained dependences are in agreement with the available experimental data.