MECHANICAL BEHAVIOR OF MOLYBDENUM DISILICIDE-BASED ALLOYS

MISRA, A; SHARIF, A

doi:10.1557/PROC-646-N4.7.1

Title: MECHANICAL BEHAVIOR OF MOLYBDENUM DISILICIDE-BASED ALLOYS

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Abstract

We have investigated the mechanical behavior of the following single-phase polycrystalline alloys with the MoSi{sub 2} body-center tetragonal structure: MoSi{sub 2} alloyed with {approximately}2.5 at.% Re, MoSi{sub 2} alloyed with 2 at.% Al, MoSi{sub 2} alloyed with 1 at.% Nb, and MoSi{sub 2} alloyed with 1 at.% Re and 2 at.% Al. Several anomalies in the mechanical behavior of alloyed materials were observed. For example, (1) addition of only {approximately}2.5 at. % Re results in an order of magnitude increase in compressive strength at 1600 C, (2) additions of Nb and Al cause solution softening at near-ambient temperatures, and (3) quaternary MoSi{sub 2}-Re-Al alloys show strengthening at elevated temperatures and reduction in flow stress with enhanced plasticity at near-ambient temperatures in compression. The mechanisms of anomalous solution hardening and softening are discussed.

Authors:: MISRA, A; SHARIF, A

Publication Date:: Fri Dec 01 00:00:00 EST 2000

Research Org.:: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

Sponsoring Org.:: US Department of Energy (US)

OSTI Identifier:: 772831

Report Number(s):: LA-UR-00-6114
Journal ID: ISSN 0272--9172; TRN: AH200121%%68

DOE Contract Number:: W-7405-ENG-36

Resource Type:: Conference

Resource Relation:: Journal Volume: 646; Conference: Conference title not supplied, Conference location not supplied, Conference dates not supplied; Other Information: PBD: 1 Dec 2000

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; ALLOYS; COMPRESSION; FLOW STRESS; HARDENING; MOLYBDENUM; PLASTICITY

Citation Formats


                    MISRA, A, SHARIF, A, and ET AL. MECHANICAL BEHAVIOR OF MOLYBDENUM DISILICIDE-BASED ALLOYS.  United States: N. p., 2000. 
        Web.  doi:10.1557/PROC-646-N4.7.1.

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                    MISRA, A, SHARIF, A, & ET AL. MECHANICAL BEHAVIOR OF MOLYBDENUM DISILICIDE-BASED ALLOYS.  United States.  https://doi.org/10.1557/PROC-646-N4.7.1

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                    MISRA, A, SHARIF, A, and ET AL. 2000.  
        "MECHANICAL BEHAVIOR OF MOLYBDENUM DISILICIDE-BASED ALLOYS".  United States.  https://doi.org/10.1557/PROC-646-N4.7.1.  https://www.osti.gov/servlets/purl/772831.

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@article{osti_772831,

  title        = {MECHANICAL BEHAVIOR OF MOLYBDENUM DISILICIDE-BASED ALLOYS},

  author       = {MISRA, A and SHARIF, A and ET AL},

  abstractNote = {We have investigated the mechanical behavior of the following single-phase polycrystalline alloys with the MoSi{sub 2} body-center tetragonal structure: MoSi{sub 2} alloyed with {approximately}2.5 at.% Re, MoSi{sub 2} alloyed with 2 at.% Al, MoSi{sub 2} alloyed with 1 at.% Nb, and MoSi{sub 2} alloyed with 1 at.% Re and 2 at.% Al. Several anomalies in the mechanical behavior of alloyed materials were observed. For example, (1) addition of only {approximately}2.5 at. % Re results in an order of magnitude increase in compressive strength at 1600 C, (2) additions of Nb and Al cause solution softening at near-ambient temperatures, and (3) quaternary MoSi{sub 2}-Re-Al alloys show strengthening at elevated temperatures and reduction in flow stress with enhanced plasticity at near-ambient temperatures in compression. The mechanisms of anomalous solution hardening and softening are discussed.},

  doi          = {10.1557/PROC-646-N4.7.1},

  url          = {https://www.osti.gov/biblio/772831},
  journal      = {},

  issn         = {0272--9172},

  number       = ,

  volume       = 646,

  place        = {United States},

  year         = {Fri Dec 01 00:00:00 EST 2000},

  month        = {Fri Dec 01 00:00:00 EST 2000}

}

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