STP956: Investigation of Neutron Irradiated Reactor Pressure Vessel Steel by Positron Annihilation and Electron Microscopy

    Sastry Viswanathan, B
    Scientific officers, Materials Science Laboratory, Indira Gandhi Centre for Atomic Research, Tamil Nadu,

    Pachur, D
    Research physicist, Kernforschungsanlage Jülich, Jülich,

    Nandedkar, RV
    Scientific officers, Materials Science Laboratory, Indira Gandhi Centre for Atomic Research, Tamil Nadu,

    Pages: 10    Published: Jan 1987


    Abstract

    Positron lifetime, annihilation line shape, and electron microscopic measurements have been carried out on neutron irradiated pressure vessel steel (HSST Plate 03) meeting ASTM A533-B (Unified Numbering System [UNS] K12539). The positron annihilation parameters for specimens irradiated at 423 K to a dose of 1.5 × 1018 n/cm2 are found to decrease sharply during the post-irradiation annealing interval, 473 to 623 K. This correlates well with the stage seen in the recovery of Vickers hardness. On the basis of known evidence for carbon migration in α-iron and the interpretation of present results, enhancement and recovery of radiation hardening have been qualitatively understood in terms of formation and dissolution of carbon decorated vacancy complexes.

    Keywords:

    pressure vessel steel, radiation embrittlement, Vickers hardness, position lifetime, annihilation line shape, dislocation structure, carbon decorated vacancy complex


    Paper ID: STP25662S

    Committee/Subcommittee: E10.08

    DOI: 10.1520/STP25662S


    CrossRef ASTM International is a member of CrossRef.