STP400: Thermal Decomposition of Gamma-Irradiated Barium Azide

    Prout, E. G.
    Rhodes University, Grahamstown,

    Moore, D. J.
    Rhodes University, Grahamstown,

    Pages: 30    Published: Jan 1966


    The thermal decomposition of ground dehydrated barium azide has been examined. The sigmoid pressure-time plots have been fitted in the temperature range 110 to 140 C by the Avrami-Erofeyev equation, -ln (1-α) = (k1 t)4, and the contracting sphere formula in the acceleratory and decay periods respectively. Activation energies have been determined for the induction, acceleratory, and decay periods. The essential role of barium metal in the thermal decomposition has been demonstrated and a theoretical explanation of the decomposition mechanism presented. Preirradiation with γ-rays (Co60) drastically reduces the induction period and increases the velocity constants. The effects of increasing the γ-ray dose have been studied and activation energies determined. The kinetics of the main decomposition are considered to be the same as for the unirradiated salt. The processes occurring during the induction period with unirradiated and preirradiated BaN6 are different. Electrical conductivity measurements of irradiated and unirradiated pellets have been made in the temperature range 20 to 60 C. The conductivity increases after irradiation.

    Paper ID: STP44634S

    Committee/Subcommittee: E10.05

    DOI: 10.1520/STP44634S

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