Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

1 Publication

Why are hot-rolled ODS steels more prone to secondary cracking than hot-extruded ODS steels?

Das, A.; Viehrig, H.-W.; Altstadt, E.; Bergner, F.; Hoffmann, J.

Secondary cracks are known to absorb energy, retard primary crack propagation and initiate at lower loads than primary cracks. They are observed more often in hot-rolled than in hot-extruded ODS steels. In this work, the microstructural factors responsible for the same are investigated. A better understanding of these factors can lead to tailoring of improved ODS steels. Fracture toughness testing of 13Cr ODS steel in hot-rolled and in hot-extruded form were carried out. The fracture behaviour of secondary cracks was investigated using scanning electron and electron backscatter microscope. Crystallographic texture and grain morphology plays a predominant role in preventing secondary cracks in hot-extruded ODS steels. At lower temperatures, secondary cracks occur predominantly via transgranular cleavage. The fracture mode changes to ductile and intergranular at higher temperatures.

Keywords: ODS steel; nanostructured ferritic alloys; fracture behaviour; anisotropy; secondary cracking; delamination

Involved research facilities

Related publications

  • Poster
    NuMat2018: The Nuclear Materials Conference, 15.10.2018, Seattle, USA