Method for thermal processing alumina-enriched spinel single crystals

Jantzen, C M

Title: Method for thermal processing alumina-enriched spinel single crystals

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Abstract

A process for age-hardening alumina-rich magnesium aluminum spinel to obtain the desired combination of characteristics of hardness, clarity, flexural strength and toughness comprises selection of the time-temperature pair for isothermal heating followed by quenching. The time-temperature pair is selected from the region wherein the precipitate groups have the characteristics sought. The single crystal spinel is isothermally heated and will, if heated long enough pass from its single phase through two pre-precipitates and two metastable precipitates to a stable secondary phase precipitate within the spinel matrix. Quenching is done slowly at first to avoid thermal shock, then rapidly. 12 figs.

Inventors:: Jantzen, C M

Issue Date:: 1995-05-09

Research Org.:: E I Dupont De Nemours & Co Inc

OSTI Identifier:: 46308

Patent Number(s):: 5413973

Application Number:: PAN: 8-190,940

Assignee:: Dept. of Energy, Washington, DC (United States)

DOE Contract Number:: AC09-76SR00001

Resource Type:: Patent

Resource Relation:: Other Information: PBD: 9 May 1995

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; SPINELS; HEAT TREATMENTS; ALUMINIUM OXIDES; MAGNESIUM OXIDES; OPTICAL PROPERTIES; MECHANICAL PROPERTIES; MICROSTRUCTURE; MONOCRYSTALS

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                    Jantzen, C M. Method for thermal processing alumina-enriched spinel single crystals.  United States: N. p., 1995. 
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                    Jantzen, C M. Method for thermal processing alumina-enriched spinel single crystals.  United States.

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                    Jantzen, C M. Tue .  
        "Method for thermal processing alumina-enriched spinel single crystals".  United States.

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@article{osti_46308,

  title        = {Method for thermal processing alumina-enriched spinel single crystals},

  author       = {Jantzen, C M},

  abstractNote = {A process for age-hardening alumina-rich magnesium aluminum spinel to obtain the desired combination of characteristics of hardness, clarity, flexural strength and toughness comprises selection of the time-temperature pair for isothermal heating followed by quenching. The time-temperature pair is selected from the region wherein the precipitate groups have the characteristics sought. The single crystal spinel is isothermally heated and will, if heated long enough pass from its single phase through two pre-precipitates and two metastable precipitates to a stable secondary phase precipitate within the spinel matrix. Quenching is done slowly at first to avoid thermal shock, then rapidly. 12 figs.},

  doi          = {},

  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {1995},

  month        = {5}

}

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