STP956: Effects of Microstructure and Thermal Aging on Neutron Irradiation Embrittlement of 2¼Cr-1Mo Steel for a Nuclear Pressure Vessel

    Suzuki, M
    Research engineer, chief, principal engineer, and head, Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun, Ibaraki-ken,

    Fukaya, K
    Research engineer, chief, principal engineer, and head, Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun, Ibaraki-ken,

    Kodaira, T
    Research engineer, chief, principal engineer, and head, Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun, Ibaraki-ken,

    Oku, T
    Research engineer, chief, principal engineer, and head, Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun, Ibaraki-ken,

    Pages: 13    Published: Jan 1987


    Abstract

    Plate, weld, and heat-affected zone (HAZ) materials of 2¼Cr-1Mo steels, designated as ASTM A387 Grade 22 Cl.1, and Cl.2 were irradiated at around 400°C to a fluence of about 2 × 1018 n/cm2 (E > 1 MeV). A387 Grade 22 Cl.2 with bainite has a lower susceptibility to neutron irradiation embrittlement than A387 Grade 22 Cl.1 with ferrite plus bainite. The anomalous ductile to brittle transition behavior of A387 Grade 22 Cl.2 was explained by taking into account the parameter ky, which is a constant in the Cottrell-Petch equation. It is concluded that there does not exist any strong interaction between thermal aging embrittlement and neutron irradiation embrittlement.

    Keywords:

    2¼Cr-1Mo steel, neutron irradiation embrittlement, radiation anneal hardening, A387 Grade 22 Cl.1, A387 Grade 22 Cl.2, temper embrittlement, phosphorus, intergranular fracture


    Paper ID: STP25643S

    Committee/Subcommittee: E10.07

    DOI: 10.1520/STP25643S


    CrossRef ASTM International is a member of CrossRef.