Lanthana-bearing nanostructured ferritic steels via spark plasma sintering

Journal Article · Thu Dec 31 00:00:00 EST 2015 · Journal of Nuclear Materials

DOI:https://doi.org/10.1016/j.jnucmat.2015.12.035· OSTI ID:1470324

Cole, James I.  ^[1]; Alsagabi, Sultan F. ^[2]; Pasebani, Somayeh ^[3]; Charit, Indrajit ^[3]; Wu, Yaqiao ^[4]; Burns, Jatuporn ^[4]; Allahar, Kerry N. ^[4]; Butt, Darryl P. ^[4]

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1. Idaho National Lab. (INL), Idaho Falls, ID (United States); Center for Advanced Energy Studies, Idaho Falls, ID (United States)
2. Univ. of Idaho, Moscow, ID (United States); Center for Advanced Energy Studies, Idaho Falls, ID (United States); King Abdulaziz City for Science and Technology, Riyadh (Saudi Arabia)
3. Univ. of Idaho, Moscow, ID (United States); Center for Advanced Energy Studies, Idaho Falls, ID (United States)
4. Boise State Univ., Boise, ID (United States); Center for Advanced Energy Studies, Idaho Falls, ID (United States)

Here, a lanthana-containing nanostructured ferritic steel (NFS) was processed via mechanical alloying (MA) of Fe-14Cr-1Ti-0.3Mo-0.5La₂O₃ (wt.%) and consolidated via spark plasma sintering (SPS). In order to study the consolidation behavior via SPS, sintering temperature and dwell time were correlated with microstructure, density, microhardness and shear yield strength of the sintered specimens. A bimodal grain size distribution including both micron-sized and nano-sized grains was observed in the microstructure of specimens sintered at 850, 950 and1050 °C for 45 min. Significant densification occurred at temperatures greater than 950 °C with a relative density higher than 98%. A variety of nanoparticles, some enriched in Fe and Cr oxides and copious nanoparticles smaller than 10 nm with faceted morphology and enriched in La and Ti oxides were observed. After SPS at 950 °C, the number density of Cr–Ti–La–O-enriched nanoclusters with an average radius of 1.5 nm was estimated to be 1.2 × 10²⁴ m^–3. The La + Ti:O ratio was close to 1 after SPS at 950 and 1050 °C; however, the number density of nanoclusters decreased at 1050 °C. With SPS above 950 °C, the density improved but the microhardness and shear yield strength decreased due to partial coarsening of the grains and nanoparticles.

• Research Organization: Idaho National Lab. (INL), Idaho Falls, ID (United States)
• Sponsoring Organization: USDOE Office of Nuclear Energy (NE)
• Grant/Contract Number: AC07-05ID14517
• OSTI ID: 1470324
• Report Number(s): INL/JOU-16-40252-Rev000
• Journal Information: Journal of Nuclear Materials, Vol. 470, Issue C; ISSN 0022-3115
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
36 MATERIALS SCIENCE
Oxide Dispersion Strengthened
Cladding
Spark Plasma Sintering
Mechanical alloying
Powder metallurgy
Sintering
Steels
Nanostructured materials
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