Vacancy-solute clustering in FeeCr alloys after neutron irradiation

TY - JOUR

T1 - Vacancy-solute clustering in FeeCr alloys after neutron irradiation

AU - Konstantinovic, Milan

AU - Ulbricht, Andreas

AU - Brodziansky, Tomas

AU - Castin, Nicolas

AU - Malerba, Lorenzo

N1 - Score=10

PY - 2020/7/18

Y1 - 2020/7/18

N2 - Vacancy-solute clustering in neutron irradiated FeeCr alloys with various concentrations of Cr and minor solutes (Ni, Si and P) were studied by using coincidence Doppler broadening spectroscopy and small angle neutron scattering techniques. The results from both experiments, supported by an object kinetic Monte Carlo model, show in a very consistent way the existence and formation of vacancy-CrNiSiP clusters that play detrimental role in irradiation hardening. Similar solute cluster number density of about 30-50 * 1E+16cm-3 and an average diameter of about 1 nm were estimated for all alloys containing minor solutes, irrespectively of the chromium content. In Fe9Cr ferritic and Fe9Cr ferritic/martensitic alloys, with significantly reduced concentration of minor solute elements, the main defects are vacancy clusters, with an average cluster size of about 10 and 2 vacancies, respectively. Large concentration of a’-precipitates was observed in Fe14Cr(NiSiP). However, both vacancy clusters and a’-precipitates provide significantly less impact to hardening in comparison to vacancy-CrNiSiP clusters. The fact that vacancyclustering in Fe9Cr ferritic alloy resembles that of pure iron suggests that Cr solutes may play lesser role in irradiation hardening of ferritic alloys and steels than previously believed.

AB - Vacancy-solute clustering in neutron irradiated FeeCr alloys with various concentrations of Cr and minor solutes (Ni, Si and P) were studied by using coincidence Doppler broadening spectroscopy and small angle neutron scattering techniques. The results from both experiments, supported by an object kinetic Monte Carlo model, show in a very consistent way the existence and formation of vacancy-CrNiSiP clusters that play detrimental role in irradiation hardening. Similar solute cluster number density of about 30-50 * 1E+16cm-3 and an average diameter of about 1 nm were estimated for all alloys containing minor solutes, irrespectively of the chromium content. In Fe9Cr ferritic and Fe9Cr ferritic/martensitic alloys, with significantly reduced concentration of minor solute elements, the main defects are vacancy clusters, with an average cluster size of about 10 and 2 vacancies, respectively. Large concentration of a’-precipitates was observed in Fe14Cr(NiSiP). However, both vacancy clusters and a’-precipitates provide significantly less impact to hardening in comparison to vacancy-CrNiSiP clusters. The fact that vacancyclustering in Fe9Cr ferritic alloy resembles that of pure iron suggests that Cr solutes may play lesser role in irradiation hardening of ferritic alloys and steels than previously believed.

KW - Neutron irradiation

KW - FeCr alloys

KW - FeCr steels

UR - https://ecm.sckcen.be/OTCS/llisapi.dll/overview/42749882

U2 - 10.1016/j.jnucmat.2020.152341

DO - 10.1016/j.jnucmat.2020.152341

M3 - Article

VL - 540

SP - 1

EP - 8

JO - Journal of Nuclear Materials

JF - Journal of Nuclear Materials

SN - 0022-3115

M1 - 152341

ER -