ODS Ferritic/martensitic alloys for Sodium Fast Reactor fuel pin cladding

The temperature dependence of strengthening mechanisms in the nanocluster-strengthened 14YWT alloy was investigated to elucidate the relative significance of contributing mechanisms in different temperature ranges This study was also aimed at providing the prediction capability of yield strength for the nanostructured ferritic alloys over a wide range of temperature The four major strengthening mechanisms: the Peierls stress, grain boundary strengthening, direct nanocluster strengthening, and dislocation forest hardening, were taken into account in the calculation, and their roles and characteristics in different temperature ranges were extensively discussed The results indicated that the contribution of grain boundary strengthening to total strengthening was the most significant component Yield strength calculation was made by combining all the strengthening components and the results were compared with the experimental data Further, the validation of the proposed approach was attempted by applying to the yield strength of other alloys

Temperature dependence of strengthening mechanisms in the nanostructured ferritic alloy 14YWT: Part II—Mechanistic models and predictions

Influence of microstructural parameters on the mechanical properties of oxide dispersion strengthened Fe-14Cr steels

Study of the deformation mechanisms in a Fe–14% Cr ODS alloy

This paper presents experimental results on the mechanical and microstructural behaviors of the nanostructured ferritic alloy 14YWT and provides discussion relevant to deformation mechanisms over a wide range of temperature. The temperature dependence of strength was investigated over a wide temperature range of −196 to 1000 °C. Detailed microstructural characterization before and after deformation was conducted to obtain the key information on deformation mechanisms; microstructural information before and after tensile deformation, including crystallographic texture, dislocation structures, and nanoclusters, was obtained from the focused ion beam lift-out specimens using EBSD, TEM, and APT techniques. Multiple deformation stages could be identified in the yield strength versus temperature curve. The dislocation structures in the specimens deformed at room temperature and at 900 °C were found to be significantly different. EBSD results were used to elucidate changes in the crystallographic textures of the specimens before and after deformation at 900 °C.

P. Bonnaillie

Papers

Tensile properties and deformation mechanisms of a 14Cr ODS ferritic steel