Designing a high Si reduced activation ferritic/martensitic steel for nuclear power generation by using Calphad method

Abstract A high Si reduced activation ferritic/martensitic (RAFM) steel for nuclear structure application is successfully designed by using Calphad method. The main designed chemical composition is C 0.18–0.22%, Cr 10.0–10.5%, W 1.0–1.5%, Si 1.0–1.3%, V+Ta 0.30–0.45%, and Fe in balance. High Si design brings excellent corrosion resistance, while low activation is advantageous in the nuclear waste processing. The experimental results indicate that the newly designed high Si RAFM steel had full martensitic structure and uniformly distributed fine second phase particles, and exhibited excellent mechanical properties and corrosion resistance. Compared to the P91 steel, this new RAFM steel designed by Calphad method is expected to be a promising candidate used in nuclear power generation, which also provides a new and effective approach to the development of RAFM steel for nuclear application.