Evaluation of the Role of Cr, Ni, Mn and Si Si in Reactor Pressure Vessel Steel

Abstract

In this paper we report initial results from a study focused on investigation of the role of elements as Cr, Ni, Mn and Si in the radiation stability of reactor pressure vessel steels. Twelve model ferritic steels with basic composition derivated from Russian WWER-1000 and Western PWR reactor pressure vessel materials were studied by Charpy-V impact, magnetic Barkhausen noise, Vickers hardness tests, Relative Seebeck Coefficient measurements and Positron annihilation spectroscopy. Higher Cr content in model steels was found generally to give increased root mean square values independent of Mn and Si contents. The ductile¿brittle transition temperatures and hardness values of the model steels were found to be independent of composition. The correlation between ductile¿brittle transition temperatures and hardness values has potential for prompt determination of the effect of composition and irradiation on the steel properties. The next stage of the assessment will study the effect of irradiation of the model steels to accumulated neutron fluences of 10e19 n.cm-2.JRC.DDG.F.4-Safety of future nuclear reactor