STP1366

    Effect of Ionizing and Displacive Components of Irradiation on the Structural Transformations in Pyrolitic Boron Nitride Ceramics

    Published: Jan 2000


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    Abstract

    The structure of pyrolitic boron nitride (BN) samples assembled to a package and irradiated with protons has been studied with Raman spectroscopy and X-ray diffraction. Shift and change of shape of X-ray bands and change of Raman band shape have been found to correlate with the calculated values of energy losses along the proton track. Ionizing constituent of irradiation is responsible for a change of the state of grain boundaries and partial recrystallization of pyrolitic BN. Displacive constituent of irradiation is responsible for stacking fault formation in the grains. A mechanism of the effect of ionizing constituent of irradiation has been introduced, where energy release on grain boundaries and break of chemical bonds on the boundaries result in partial recrystallization of the material. According to this mechanism the recrystallization is much more feasible in pre-irradiated materials.

    Keywords:

    radiation-induced structural transformations, pyrolitic boron nitride, Raman spectroscopy, X-ray diffraction


    Author Information:

    Stepanov, VA
    Head of laboratory, research scientist and professor, SSC RF — Institute of Physics and Power Engineering, Obninsk,

    Stepanov, PA
    Head of laboratory, research scientist and professor, SSC RF — Institute of Physics and Power Engineering, Obninsk,

    Chernov, VM
    Head of laboratory, research scientist and professor, SSC RF — Institute of Physics and Power Engineering, Obninsk,

    Golovinov, AV
    Research scientists, Moscow Steel and Alloys Institute, Moscow,

    Kryukova, LM
    Research scientists, Moscow Steel and Alloys Institute, Moscow,


    Paper ID: STP12454S

    Committee/Subcommittee: E10.07

    DOI: 10.1520/STP12454S


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