Model FeCrAl alloys of Fe-10%Cr-5%Al, Fe-12%Cr-4.5%Al, Fe-15%Cr-4%Al, and Fe-18%Cr-3%Al (in wt %) were irradiated with 1 MeV Kr++ ions in-situ with transmission electron microscopy to a dose of 2.5 displacements per atom (dpa) at 320 °C. In all cases, the microstructural damage consisted of dislocation loops with ½<111> and <100> Burgers vectors. The proportion of ½<111> dislocation loops varied from ~50% in the Fe-10%Cr-5%Al model alloy and the Fe-18Cr%-3%Al model alloy to a peak of ~80% in the model Fe-15%Cr-4.5%Al alloy. The dislocation loop volume density increased with dose for all alloys and showed signs of approaching an upper limit. The total loop populations at 2.5 dpa had a slight (and possibly insignificant) decline as the chromium content was increased from 10 to 15 wt %, but the Fe-18%Cr-3%Al alloy had a dislocation loop population ~50% smaller than the other model alloys. The largest dislocation loops in each alloy had image sizes of close to 20 nm in the micrographs, and the median diameters for all alloys ranged from 6 to 8 nm. Nature analysis by the inside-outside method indicated most dislocation loops were interstitial type.
"Helical dislocations: Observation of vacancy defect bias of screw dislocations in neutron irradiated Fe-9Cr"
G. Robert Odette, Jack Haley,
Acta Materialia
Vol.
2019
Link
"Microstructural examination of neutron, proton and self-ion irradiation damage in a model Fe9Cr alloy"
Jack Haley, G. Robert Odette, Steve Roberts,
Journal of Nuclear Materials
Vol. 533
2020
Link
"Microstructural examination of neutron, proton and self-ion irradiation damage in a model Fe9Cr alloy"
Jack Haley, S. de Moraes Shubeita, P. Wady, A.J. London, G. Robert Odette, S. Lozano, Steve Roberts,
Journal of Nuclear Materials
Vol. 533
2020
Link
Presentations:
"Radiation Damage with a Twist: A study of helical dislocations in irradiated FeCr alloys"
Jack Haley,
NuMat2018: The Nuclear Materials Conference
October 14-18, (2018)
Link