Processing and microstructure characterization of oxide dispersion strengthened Fe-14Cr-0.4Ti-0.25Y2O3 ferritic steels fabricated by spark plasma sintering

DOI: 10.1016/j.jnucmat.2015.04.029

Authors: Hongtao Zhang (University of Oxford) , Yina Huang (University of Oxford) , Huanpo Ning (Queen Mary University of London) , Ceri A. Williams (University of Oxford) , Andrew London (University of Oxford) , Karl Dawson (University of Liverpool) , Zuliang Hong (University of Oxford) , Michael Gorley (Culham Centre for Fusion Energy; University of Oxford) , Chris Grovenor (University of Oxford) , Gordon J. Tatlock (University of Liverpool) , Steve G. Roberts (University of Oxford) , Michael J. Reece (Queen Mary University of London) , Haixue Yan (Queen Mary University of London) , Patrick Grant (University of Oxford)
Co-authored by industrial partner: Yes

Type: Journal Paper
Journal: Journal Of Nuclear Materials

State: Published (Approved)
Published: April 2015
Diamond Proposal Number(s): 7528

Abstract: Ferritic steels strengthened with Ti–Y–O nanoclusters are leading candidates for fission and fusion reactor components. A Fe–14Cr–0.4Ti + 0.25Y2O3 (14YT) alloy was fabricated by mechanical alloying and subsequently consolidated by spark plasma sintering (SPS). The densification of the 14YT alloys significantly improved with an increase in the sintering temperature. Scanning electron microscopy and electron backscatter diffraction revealed that 14YT SPS-sintered at 1150 °C under 50 MPa for 5 min had a high density (99.6%), a random grain orientation and a bimodal grain size distribution (<500 nm and 1–20 μm). Synchrotron X-ray diffraction patterns showed bcc ferrite, Y2Ti2O7, FeO, and chromium carbides, while transmission electron microscopy and atom probe tomography showed uniformly dispersed Y2Ti2O7 nanoclusters of <5 nm diameter and number density of 1.04 × 1023 m−3. Due to the very much shorter consolidation times and lower pressures used in SPS compared with the more usual hot isostatic pressing routes, SPS is shown to be a cost-effective technique for oxide dispersion strengthened (ODS) alloy manufacturing with microstructural features consistent with the best-performing ODS alloys.

Diamond Keywords: Alloys

Subject Areas: Materials, Engineering


Instruments: I11-High Resolution Powder Diffraction

Added On: 28/04/2015 08:25

Documents:
1-s2.0-S0022311515002391-main.pdf

Discipline Tags:

Materials Engineering & Processes Materials Science Engineering & Technology Metallurgy

Technical Tags:

Diffraction X-ray Powder Diffraction