Elevated temperature microstructure evolution of a medium-entropy CrCoNi superalloy containing Al,Ti

Slone, C. E.; George, Easo; Mills, Michael J.

doi:10.1016/j.jallcom.2019.152777

Title: Elevated temperature microstructure evolution of a medium-entropy CrCoNi superalloy containing Al,Ti

Abstract

A new medium-entropy superalloy was produced based on the compositions of equiatomic CrCoNi and Ni-base superalloy Inconel 740H. Initial alloy design was performed using Thermo-Calc. The aging response and microstructural stability were assessed following heat treatment at temperatures between 600 and 900 °C and durations up to 100 h. Aging from a fully recrystallized state resulted in negligible grain growth and produced γ’ and σ phases. The same phases were present after aging from a cold-rolled state, but partially recrystallized microstructures resulted in multi-modal size distributions and heterogeneous spatial arrangements. Finally, room temperature hardness measurements were used to correlate aging conditions with quantitative precipitate measurements and mechanical properties.

Authors:

Slone, C. E. ^[1];

^[2]; Mills, Michael J. ^[3]

The Ohio State Univ., Columbus, OH (United States)
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)
Ohio State Univ., Columbus, OH (United States)

Publication Date:: Thu Oct 24 00:00:00 EDT 2019

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

Sponsoring Org.:: USDOE Office of Science (SC), Basic Energy Sciences (BES); National Science Foundation (NSF)

OSTI Identifier:: 1607024

Grant/Contract Number:: AC05-00OR22725; DMR-1508505; DMR-1905748; DGE-1343012

Resource Type:: Accepted Manuscript

Journal Name:: Journal of Alloys and Compounds

Additional Journal Information:: Journal Volume: 817; Journal Issue: C; Journal ID: ISSN 0925-8388

Publisher:: Elsevier

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; medium-entropy alloy; CrCoNi; Ni-base superalloy; microstructural stability; phase decomposition

Citation Formats


                    Slone, C. E., George, Easo, and Mills, Michael J. Elevated temperature microstructure evolution of a medium-entropy CrCoNi superalloy containing Al,Ti.  United States: N. p., 2019. 
Web.  doi:10.1016/j.jallcom.2019.152777.

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                    Slone, C. E., George, Easo, & Mills, Michael J. Elevated temperature microstructure evolution of a medium-entropy CrCoNi superalloy containing Al,Ti.  United States.  https://doi.org/10.1016/j.jallcom.2019.152777

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                    Slone, C. E., George, Easo, and Mills, Michael J. Thu .  
"Elevated temperature microstructure evolution of a medium-entropy CrCoNi superalloy containing Al,Ti".  United States.  https://doi.org/10.1016/j.jallcom.2019.152777.  https://www.osti.gov/servlets/purl/1607024.

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@article{osti_1607024,

  title        = {Elevated temperature microstructure evolution of a medium-entropy CrCoNi superalloy containing Al,Ti},

  author       = {Slone, C. E. and George, Easo and Mills, Michael J.},

  abstractNote = {A new medium-entropy superalloy was produced based on the compositions of equiatomic CrCoNi and Ni-base superalloy Inconel 740H. Initial alloy design was performed using Thermo-Calc. The aging response and microstructural stability were assessed following heat treatment at temperatures between 600 and 900 °C and durations up to 100 h. Aging from a fully recrystallized state resulted in negligible grain growth and produced γ’ and σ phases. The same phases were present after aging from a cold-rolled state, but partially recrystallized microstructures resulted in multi-modal size distributions and heterogeneous spatial arrangements. Finally, room temperature hardness measurements were used to correlate aging conditions with quantitative precipitate measurements and mechanical properties.},

  doi          = {10.1016/j.jallcom.2019.152777},

  journal      = {Journal of Alloys and Compounds},

  number       = C,

  volume       = 817,

  place        = {United States},

  year         = {Thu Oct 24 00:00:00 EDT 2019},

  month        = {Thu Oct 24 00:00:00 EDT 2019}

}

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Journal Article:

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https://doi.org/10.1016/j.jallcom.2019.152777

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Cited by: 8 works

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Figures / Tables:

Table 1: Composition of alloy V1.

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