TY - JOUR
T1 - Critical assessment of Cr-rich precipitates in neutron-irradiated Fe–12 at%Cr: Comparison of SANS and APT
AU - Bergner, Frank
AU - Pareige, Cristelle
AU - Kuksenko, Vladimir
AU - Malerba, Lorenzo
AU - Pareige, Philippe
AU - Ulbricht, Andreas
AU - Wagner, Arne
A2 - Bonny, Giovanni
N1 - Score = 10
PY - 2013/10
Y1 - 2013/10
N2 - Neutron irradiation at 300 C up to 0.6 dpa of an industrial purity Fe–12at%Cr alloy gives rise to the formation
of Cr-rich precipitates of radii of about 1 nm. Small-angle neutron scattering (SANS) and atom
probe tomography (APT) applied to the same material should reveal consistent characteristics of the irradiation-
induced features. They roughly do so with respect to size and volume fraction, but they do not
with respect to the composition of the precipitates or clusters. The discrepancy was expressed in terms
of the Porod invariant of nuclear SANS. This quantity can be determined directly by integrating the measured
nuclear difference scattering cross section or, alternatively, estimated from the APT results. Both
estimates were compared taking into account all potential sources of deviation including error propagation.
We have found that the deviation is significant and can be progressively removed by artificially
reducing the Fe fraction in the Cr-rich clusters with respect to the measured value. A well-known effect
of this kind is the different evaporation fields of Cr-rich clusters and the Fe-rich matrix and resulting ion
trajectory overlaps in APT. State-of-the-art consideration of this effect indicates, however, that it is not
sufficient to remove the observed discrepancy.
AB - Neutron irradiation at 300 C up to 0.6 dpa of an industrial purity Fe–12at%Cr alloy gives rise to the formation
of Cr-rich precipitates of radii of about 1 nm. Small-angle neutron scattering (SANS) and atom
probe tomography (APT) applied to the same material should reveal consistent characteristics of the irradiation-
induced features. They roughly do so with respect to size and volume fraction, but they do not
with respect to the composition of the precipitates or clusters. The discrepancy was expressed in terms
of the Porod invariant of nuclear SANS. This quantity can be determined directly by integrating the measured
nuclear difference scattering cross section or, alternatively, estimated from the APT results. Both
estimates were compared taking into account all potential sources of deviation including error propagation.
We have found that the deviation is significant and can be progressively removed by artificially
reducing the Fe fraction in the Cr-rich clusters with respect to the measured value. A well-known effect
of this kind is the different evaporation fields of Cr-rich clusters and the Fe-rich matrix and resulting ion
trajectory overlaps in APT. State-of-the-art consideration of this effect indicates, however, that it is not
sufficient to remove the observed discrepancy.
KW - Radiation-induced precipitation
KW - Fe-Cr alloys
KW - SANS
KW - APT
UR - http://ecm.sckcen.be/OTCS/llisapi.dll/open/ezp_131791
UR - http://knowledgecentre.sckcen.be/so2/bibref/10694
U2 - 10.1016/j.jnucmat.2013.05.023
DO - 10.1016/j.jnucmat.2013.05.023
M3 - Article
SN - 0022-3115
VL - 442
SP - 463
EP - 469
JO - Journal of Nuclear Materials
JF - Journal of Nuclear Materials
IS - 1-3
ER -