Understanding irradiation-induced nanoprecipitation in zirconium alloys using parallel TEM and APT

JOURNAL OF NUCLEAR MATERIALS

卷:510

Article

Harte, A.¹  Babu, R. Prasath¹  Hirst, C. A.²  Martin, T. L.²  Bagot, P. A. J.²  Moody, M. P.²  Frankel, P.¹  Romero, J.³  Hallstadius, L.⁴  Darby, E. C.⁵  Preuss, M.¹ 

[1] Univ Manchester, Sch Mat, Oxford Rd, Manchester M13 9PL, Lancs, England

[2] Univ Oxford, Dept Mat, Parks Rd, Oxford OX1 3PH, England

[3] Westinghouse Elect Co, Columbia, SC USA

[4] Westinghouse Elect Sweden AB, SE-72163 Vasteras, Sweden

[5] Rolls Royce Plc, Nucl Mat, Derby, England

关键词: Nano precipitation;    Transmission electron microscopy;    Atom probe tomography;    Zirconium;    Irradiation;   

DOI  :  10.1016/j.jnucmat.2018.08.033

来源: Elsevier

【 摘 要 】

We investigate nano-scale irradiation-induced precipitation in a Zr-Sn-Fe-Cr-Ni-alloy (Zircaloy-2) by combining atom probe tomography (APT) for chemical detail with scanning transmission electron microscopy (STEM) and high resolution energy dispersive X-ray (EDX) spectroscopy for wider context and complimentary and correlative TEM diffraction techniques for crystallographic relationships. We find that Fe- and Cr-rich nano-rods precipitate in Zircaloy-2 following proton irradiation at 350 degrees C to a low dose of similar to 2 dpa. The long-axis of the nano-rods are aligned in a direction 12-15 degrees from the Zr matrix < 0001 >, align in the basal plane and are of width 1.5-5 nm. Smaller rods are of APT-determined composition Zr-4(Fe0.67Cr0.33), tending towards Zr-3(Fe0.69Cr0.31) as the rod volume increases to > similar to 400 nm(3), in agreement with STEM-EDX determination of composition resembling that of Zr3Fe with Cr replacing some of the Fe. The Fe/Cr ratio has been shown to increase with distance from the nearest partially-dissolved Zr(Fe,Cr)(2) phase particle. The nucleation of nano rods has implications for macroscopic irradiation-induced deformation phenomena, irradiation-induced hardening and the evolution of dislocation loops and other defects. (C) 2018 Published by Elsevier B.V.

【 授权许可】

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