Oxidation/dissolution of ferritic ODS steels in static lead with various oxygen content at 650 °C

Corrosion behaviour of oxide dispersion strengthened iron‐chromium steels in liquid lead at 973 K

“…obtained under the same conditions). However, the present results can be considered to be consistent with those obtained at slightly lower temperatures and with an oxygen concentration that is in the same domain …”

“…longer time of exposure (2000 h), higher temperature (973 K) and an oxygen content (10 −4 –10 −5 wt% O) laying at the borderline between the passivation (or the so‐called “oxygen‐added Pb” regime) and saturation regimes, an initial formation of an outer magnetite layer may be supposed, although it was never detected by EDX analysis. Furthermore, Tsisar et al demonstrated that the interaction mode of 13Cr‐ODS or 14Cr‐ODS steels with a Pb melt at 923 K depends on the oxygen concentration in the liquid metal, which changes from its dissolution in lead, when the oxygen content in the melt is C O ≤ 10 −14 , to the formation of a protective oxide layer on the surface of steel when the oxygen concentration is approximately between 10 −6 and 10 −4 (all in wt% O). The latter is the so‐called “oxygen‐added Pb” regime .…”

“…Furthermore, Tsisar et al demonstrated that the interaction mode of 13Cr‐ODS or 14Cr‐ODS steels with a Pb melt at 923 K depends on the oxygen concentration in the liquid metal, which changes from its dissolution in lead, when the oxygen content in the melt is C O ≤ 10 −14 , to the formation of a protective oxide layer on the surface of steel when the oxygen concentration is approximately between 10 −6 and 10 −4 (all in wt% O). The latter is the so‐called “oxygen‐added Pb” regime . Under these conditions neither a severe oxidation accompanied by the formation of a thick multilayer scale nor the dissolution of the steel with intergranular penetration of liquid Pb has occurred, as was also observed in the present investigation.…”

“…The literature data on the corrosion behaviour of ODS steels with nominally 8 ÷ 13 wt% Cr, tested in HLM with a dissolved oxygen concentration ranging from 10 −6 to 10 −3 wt%, indicate the formation of a double oxide layer constituted by a spinel in the inner part and magnetite in the external part, whose stability depends on the oxygen content in the liquid metal. The oxidation/corrosion behaviour of 9Cr‐ODS, 12Cr‐ODS, 13Cr‐ODS and 14Cr‐ODS steels in a lead bath under stagnant conditions, for temperatures lower than 923 K and for different oxygen contents has been investigated recently. The formation of Fe‐Cr spinel type oxides on the tested steel samples has been observed to be independent of Cr content, but the oxide scales morphologies and their thickness are strongly dependent on the operating temperature and oxygen content …”

“…The oxidation/corrosion behaviour of 9Cr‐ODS, 12Cr‐ODS, 13Cr‐ODS and 14Cr‐ODS steels in a lead bath under stagnant conditions, for temperatures lower than 923 K and for different oxygen contents has been investigated recently. The formation of Fe‐Cr spinel type oxides on the tested steel samples has been observed to be independent of Cr content, but the oxide scales morphologies and their thickness are strongly dependent on the operating temperature and oxygen content …”