Development of castable nanostructured alloys as a new generation RAFM steels

Tan, Lizhen; Katoh, Yutai; Snead, Lance L.

doi:10.1016/j.jnucmat.2018.05.024

Title: Development of castable nanostructured alloys as a new generation RAFM steels

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Abstract

Castable nanostructured alloys (CNAs) are being developed as a new generation of reduced-activation ferritic-martensitic (RAFM) steels to overcome certain limitations of the current RAFM steels, such as their narrow operating temperature range and associated low strength at high temperatures. Six CNAs were developed and examined, exhibiting noticeably increased yield strength, tensile strength and creep resistance as compared to the current RAFM steels, which are comparable to ODS-Eurofer (0.3% Y₂O₃) at 650 °C. The enhanced strength of CNAs is also associated with a beneficial increase in Charpy impact upper-shelf energies, up to ~2.5 times that of the current RAFM steels, with comparable ductile-brittle transition temperatures. Furthermore, a broad analysis of microstructure, alloy chemistry and grain size analyses clearly support the mechanisms that explain the mechanical property improvements of these CNAs, providing essential insight for further development of advanced RAFM steels to meet the challenges of future fusion reactors.

Authors:

^[1];

^[1]; Snead, Lance L. ^[2]

Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Stony Brook Univ., Stony Brook, NY (United States)

Publication Date:: 2018-05-09

Research Org.:: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:: USDOE Office of Science (SC)

OSTI Identifier:: 1479784

Alternate Identifier(s):: OSTI ID: 1693646

Grant/Contract Number:: AC05-00OR22725

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Nuclear Materials

Additional Journal Information:: Journal Volume: 511; Journal Issue: C; Journal ID: ISSN 0022-3115

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; Tensile; Creep; Charpy; Nanoprecipitates; Sink strength

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                    Tan, Lizhen, Katoh, Yutai, and Snead, Lance L. Development of castable nanostructured alloys as a new generation RAFM steels.  United States: N. p., 2018. 
Web.  doi:10.1016/j.jnucmat.2018.05.024.

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                    Tan, Lizhen, Katoh, Yutai, & Snead, Lance L. Development of castable nanostructured alloys as a new generation RAFM steels.  United States.  https://doi.org/10.1016/j.jnucmat.2018.05.024

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                    Tan, Lizhen, Katoh, Yutai, and Snead, Lance L. Wed .  
"Development of castable nanostructured alloys as a new generation RAFM steels".  United States.  https://doi.org/10.1016/j.jnucmat.2018.05.024.  https://www.osti.gov/servlets/purl/1479784.

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@article{osti_1479784,

  title        = {Development of castable nanostructured alloys as a new generation RAFM steels},

  author       = {Tan, Lizhen and Katoh, Yutai and Snead, Lance L.},

  abstractNote = {Castable nanostructured alloys (CNAs) are being developed as a new generation of reduced-activation ferritic-martensitic (RAFM) steels to overcome certain limitations of the current RAFM steels, such as their narrow operating temperature range and associated low strength at high temperatures. Six CNAs were developed and examined, exhibiting noticeably increased yield strength, tensile strength and creep resistance as compared to the current RAFM steels, which are comparable to ODS-Eurofer (0.3% Y2O3) at 650 °C. The enhanced strength of CNAs is also associated with a beneficial increase in Charpy impact upper-shelf energies, up to ~2.5 times that of the current RAFM steels, with comparable ductile-brittle transition temperatures. Furthermore, a broad analysis of microstructure, alloy chemistry and grain size analyses clearly support the mechanisms that explain the mechanical property improvements of these CNAs, providing essential insight for further development of advanced RAFM steels to meet the challenges of future fusion reactors.},

  doi          = {10.1016/j.jnucmat.2018.05.024},

  journal      = {Journal of Nuclear Materials},

  number       = C,

  volume       = 511,

  place        = {United States},

  year         = {2018},

  month        = {5}

}

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