Changes in near-surface microstructure of metallic limiters following one year of service in Doublet III

Trester, P. W.; Sevier, D. L.; Sabado, M. M.

Title: Changes in near-surface microstructure of metallic limiters following one year of service in Doublet III

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Abstract

The structural alloys Ta-10W, Mo, and Inconel X-750 were used for plasma limiters during the 3-MW ohmic heating experiments of the Doublet III tokamak. Post-service examinations of these limiters are reviewed. Near-surface melting, cracking, and microstructural changes are shown and discussed. During III service, elements from other metallic components were transported by the plasma and deposited on the limiter surface; significantly, high concentrations of Ni, Fe, Mo, and C were detected in the regions found to be microcracked in the Ta-10W. Observations and analyses are made that are relevant to the design of limiter and armor components for larger tokamaks.

Authors:: Trester, P. W.; Sevier, D. L.; Sabado, M. M.

Publication Date:: Sat Aug 01 00:00:00 EDT 1981

Research Org.:: General Atomic Co., San Diego, CA (USA)

OSTI Identifier:: 6221056

Report Number(s):: GA-A-16429; CONF-810831-35
ON: DE81029487; TRN: 81-016433

DOE Contract Number:: AT03-76ET51011

Resource Type:: Conference

Resource Relation:: Conference: Fusion reactor materials meeting, Seattle, WA, USA, 9 Aug 1981

Country of Publication:: United States

Language:: English

Subject:: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 36 MATERIALS SCIENCE; DOUBLET REACTORS; LIMITERS; INCONEL X750; MICROSTRUCTURE; MOLYBDENUM; TANTALUM ALLOYS; TUNGSTEN ALLOYS; CRACKS; MELTING; ALLOYS; CHROMIUM ALLOYS; CRYSTAL STRUCTURE; ELEMENTS; INCONEL ALLOYS; IRON ALLOYS; METALS; NICKEL ALLOYS; NICKEL BASE ALLOYS; PHASE TRANSFORMATIONS; REFRACTORY METALS; THERMONUCLEAR REACTORS; TITANIUM ALLOYS; TOKAMAK TYPE REACTORS; TRANSITION ELEMENTS; 700209* - Fusion Power Plant Technology- Component Development & Materials Testing; 360106 - Metals & Alloys- Radiation Effects

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                    Trester, P. W., Sevier, D. L., and Sabado, M. M. Changes in near-surface microstructure of metallic limiters following one year of service in Doublet III.  United States: N. p., 1981. 
        Web.

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                    Trester, P. W., Sevier, D. L., & Sabado, M. M. Changes in near-surface microstructure of metallic limiters following one year of service in Doublet III.  United States.

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                    Trester, P. W., Sevier, D. L., and Sabado, M. M. 1981.  
        "Changes in near-surface microstructure of metallic limiters following one year of service in Doublet III".  United States.  https://www.osti.gov/servlets/purl/6221056.

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@article{osti_6221056,

  title        = {Changes in near-surface microstructure of metallic limiters following one year of service in Doublet III},

  author       = {Trester, P. W. and Sevier, D. L. and Sabado, M. M.},

  abstractNote = {The structural alloys Ta-10W, Mo, and Inconel X-750 were used for plasma limiters during the 3-MW ohmic heating experiments of the Doublet III tokamak. Post-service examinations of these limiters are reviewed. Near-surface melting, cracking, and microstructural changes are shown and discussed. During III service, elements from other metallic components were transported by the plasma and deposited on the limiter surface; significantly, high concentrations of Ni, Fe, Mo, and C were detected in the regions found to be microcracked in the Ta-10W. Observations and analyses are made that are relevant to the design of limiter and armor components for larger tokamaks.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/6221056},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Sat Aug 01 00:00:00 EDT 1981},

  month        = {Sat Aug 01 00:00:00 EDT 1981}

}

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