Development of RAFM steel for nuclear applications with reduced manganese, silicon and carbon content

In this work, we investigate an alternative route for the production of reduced activation ferritic-martensitic (RAFM) steels with reduced contents of manganese and carbon. Alternation of the chemical composition coupled with various heat treatments as well as quench & rolling procedures are applied in an attempt to reduce the DBTT without altering the nominal strength and ductility. The obtained experimental results on the mechanical properties and microstructural analysis are compared to the reference European RAFM steel i.e. Eurofer97. It is demonstrated that an alternation of the conventional heat treatment of the newly developed low Mn/C steel allows the production of a material with a ductile to brittle transition temperature as low as -133 ◦C and strength comparable to that of Eurofer97. On the other hand, the performed quench & rolling procedure does not lead to any noticeable reduction of the DBTT, albeit it significantly increases the tensile strength without compromising the ductility in the relevant operational temperature range.