Accurate quantitative EDS-TEM analysis of precipitates and matrix in equilibrium (α plus β) Zr-1Nb alloys with Ta addition

[摘要] The (alpha+beta) phase microstructure in Zr-1.05Nb, Zr-0.85Nb-0.20Ta and Zr-0.85Nb-0.40Ta (wt.%) alloys annealed at 570 degrees C for 3840 h after beta-quenching were observed at different scales by optical, SEM and TEM microscopies. A quantitative study of phase chemical compositions was carried out by EDS-TEM with experimental Cliff-Lorimer factors. The alpha matrix was measured on thin films and the beta particle on carbon extractive replicas. The Ta addition showed a continuous increase of (Nb + Ta) solubility in alpha-Zr and (Zr + Ta) solubility in the beta-Nb phase. The increase of Ta in the nominal composition of the Zr-(Nb, Ta) alloy causes the decrease of the mass fraction of beta-Nb phase. (C) 2020 Elsevier B.V. All rights reserved.

[发布日期] 2020-12-20

[关键词] Zr-Nb alloys;Ta addition;Transmission electron microscopy (TEM);Energy dispersive X-ray spectroscopy (EDS);Cliff-lorimer factor