[2H18-22] Influence of materials in Severe accident

[2H19] Effects of heating on the strength and the microstructure of the reactor materials during severe accident

(2)Estimation of the heating effects on the strength of containment vessel steels of the damaged Fukushima Daiichi nuclear plants

*Kengo Hashimoto¹, keita Yoshinaga¹, Yuto Aoki¹, Shiro Jitsukawa¹ (1. Nitional Institute of Technology Fukushima college)

Keywords:Fukushima Daiichi, Reactor decommissioning, Strength of the Containment vessel steel, Effect of temperature history

Temperature of the containment vessels of the Fukushima Diiichi plant increased to some hundreds of degrees (in C) during the severe accident. This might introduce the changes of the strength properties of CV steels. Various thermal aging with different cooling rate are made on the steel test specimens. To estimate the property changes of the temperature change by the accident, tensile and fracture toughness are evaluated.