Copper precipitation in Fe–Cu alloys under electron and neutron irradiation

• Published in: Acta materialia Vol. 52; no. 4; pp. 877 - 886
• Main Authors: Barashev, A.V., Golubov, S.I., Bacon, D.J., Flewitt, P.E.J., Lewis, T.A.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 23.02.2004; Elsevier Science
• Subjects: Coarsening; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Electrons and positron radiation effects; Exact sciences and technology; Ferritic steels; Hardening; Materials science; Mean Field Analysis; Neutron radiation effects; Physical radiation effects, radiation damage; Physics; Precipitation; Radiation treatment (particle and electromagnetic); Radiation treatments; Structure of solids and liquids; crystallography; Treatment of materials and its effects on microstructure and properties; 81.30.Mh; Ferritic steels; Hardening; Precipitation; 64.75+g; 61.80.Az; 61.80.Hg; 61.82.Bg; Coarsening; Mean Field Analysis; Radiation effects; Theoretical study; Copper additions; 81.30.Mh Ferritic steels; Precipitation hardening; Precipitates; Phase transitions; Binary alloys; Electron irradiation; Binding energy; Neutron irradiation; Copper; Iron base alloys
• ISSN: 1359-6454; 1873-2453
• DOI: 10.1016/j.actamat.2003.10.023

Precipitation of copper-rich clusters is a contribution to in-service hardening of some reactor pressure vessel ferritic steels. At temperatures less than 300 °C the precipitates are observed to be about 2 nm in diameter and not to coarsen, at least in the dose range from ∼10 −3 to 10 −2 dpa. As a result the hardening is close to a maximum. This phenomenon is studied here by computer simulations based on the “mean-field” approach for describing microstructural evolution in a binary Fe–Cu alloy. It is shown that the experimental data obtained from electron irradiated material and reactor-neutron irradiated steels have a stage of precipitate evolution intermediate between growth and coarsening. During this stage the size distribution of precipitates broadens while the number density and the mean size remain constant, which explains the observations. The role interstitial atom clusters produced in displacement cascades may have on the kinetics of copper precipitate coarsening is discussed.