Nitriding of super alloys for enhancing physical properties

Title: Nitriding of super alloys for enhancing physical properties

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Abstract

The invention teaches the improvement of certain super alloys by exposing the alloy to an atmosphere of elemental nitrogen at elevated temperatures in excess of 750.degree. C. but less than 1150.degree. C. for an extended duration, viz., by nitriding the surface of the alloy, to establish barrier nitrides of the order of 25-100 micrometers thickness. These barrier nitrides appear to shield the available oxidizing metallic species of the alloy for up to a sixfold improved resistance against oxidation and also appear to impede egress of surface dislocations for increased fatigue and creep strengths.

Inventors:

Purohit, Ankur ^[1]

Lisle, IL

Publication Date:: 1986-01-01

Research Org.:: Argonne National Lab. (ANL), Argonne, IL (United States)

OSTI Identifier:: 865846

Patent Number(s):: US 4588450

Assignee:: United States of America as represented by United States (Washington, DC)

DOE Contract Number:: W-31109-ENG-38

Resource Type:: Patent

Country of Publication:: United States

Language:: English

Subject:: nitriding; super; alloys; enhancing; physical; properties; teaches; improvement; exposing; alloy; atmosphere; elemental; nitrogen; elevated; temperatures; excess; 750; degree; 1150; extended; duration; viz; surface; establish; barrier; nitrides; 25-100; micrometers; thickness; appear; shield; available; oxidizing; metallic; species; sixfold; improved; resistance; oxidation; impede; egress; dislocations; increased; fatigue; creep; strengths; physical properties; elevated temperatures; elevated temperature; improved resistance; metallic species; micrometers thick; elemental nitrogen; super alloys; super alloy; /148/

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                    Purohit, Ankur. Nitriding of super alloys for enhancing physical properties.  United States: N. p., 1986. 
        Web.

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                    Purohit, Ankur. Nitriding of super alloys for enhancing physical properties.  United States.

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                    Purohit, Ankur. Wed .  
        "Nitriding of super alloys for enhancing physical properties".  United States.  https://www.osti.gov/servlets/purl/865846.

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@article{osti_865846,

  title        = {Nitriding of super alloys for enhancing physical properties},

  author       = {Purohit, Ankur},

  abstractNote = {The invention teaches the improvement of certain super alloys by exposing the alloy to an atmosphere of elemental nitrogen at elevated temperatures in excess of 750.degree. C. but less than 1150.degree. C. for an extended duration, viz., by nitriding the surface of the alloy, to establish barrier nitrides of the order of 25-100 micrometers thickness. These barrier nitrides appear to shield the available oxidizing metallic species of the alloy for up to a sixfold improved resistance against oxidation and also appear to impede egress of surface dislocations for increased fatigue and creep strengths.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/865846},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {1986},

  month        = {1}

}

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Nitriding of super alloys for enhancing physical properties

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