Dispersion-Strengthened Ferritic Steels for Fast Neutron Reactors

Abstract

This paper describes dispersion-strengthened ferritic steel developed for fast neutron reactors. The effect of the type and amount of the hardening oxide phase on the long-term strength and structure of the material at 700 °C is examined. The data are extrapolated to 10,000 hour holding to show the long-term strength of 70 to 80 MPa. The radiation resistance of the steel is determined under ion and neutron exposure to 100 dpa (neutron fluence 2.6 • 10²³ n/cm²). The steel has high bulk stability and low sensitivity of its mechanical characteristics to radiation. The material does not lose its plasticity after the maximum exposure. The corrosion behavior of the dis-persion-strengthened steel in Na, Li, Pb, and eutectic Pb–Li melts, Pb–Bi alloys, and Cs and Te vapors is investigated. The corrosion resistance of the steel is practically always commensurable with or somewhat higher than that of the best reactor steels ÉP172 and ÉP450.