Abstract
Oxide dispersed strengthened (ODS) steels can exhibit a strongly anisotropic microstructure leading to anisotropic mechanical properties. The ductile to brittle transition temperature in the small punch (SP) test is therefore dependent on the specimen orientation. Three ODS steels with 13-14 mass percent Cr, manufactured through hot extrusion and hot rolling respectively, were investigated by means of SPT in different orientations. Existing microstructural data (EBSD) are used to discuss the anisotropic fracture behavior observed in the SPT. In addition, the SPT results are compared with those from existing fracture mechanics tests based on sub-sized C(T) samples. The applicability of the empirical conversion of SPT based transition temperatures into Charpy transition temperatures – well established for isotropic homogeneous metals – is investigated for materials with anisotropic microstructure.
Highlights
Oxide dispersion strengthened (ODS) steels are candidate materials for fuel claddings of Gen-IV sodium cooled fast reactors as well as for the first wall and blanket structures of fusion reactors [1,2,3]
In this paper we investigate one hot rolled and two hot extruded Oxide dispersed strengthened (ODS) steels by means of small punch (SP) testing
ODS-HR is a 13%Cr ODS steel hot rolled plate provided by Karlsruhe Institute of Technology, Germany (KIT)
Summary
Oxide dispersion strengthened (ODS) steels are candidate materials for fuel claddings of Gen-IV sodium cooled fast reactors as well as for the first wall and blanket structures of fusion reactors [1,2,3]. Sufficient tensile and fracture mechanical properties are required for safety relevant structural applications in the whole range from room to operation temperature. Lindau et al demonstrated that yield stress and ultimate tensile stress (UTS) of ODS-EUROFER are significantly higher in comparison to the non ODS EUROFER steel for temperatures up to 750 °C [4]. The creep resistance at 750 °C is significantly improved. The ductile-to-brittle transition temperature (DBTT) was found to be significantly higher than that of nonODS-EUROFER. Chaouadi et al [5] found a significant crack resistance degradation of Eurofer ODS when the test temperature increases. Byun et al [6] have demonstrated that high temperature fracture toughness could be significantly improved by appropriate thermo-mechanical treatments
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
