Internal stresses in pre-stressed micron-scale aluminum core-shell particles and their improved reactivity

McCollum, Jena; Pantoya, Michelle L.; Tamura, Nobumichi

doi:10.1063/1.4929642

Title: Internal stresses in pre-stressed micron-scale aluminum core-shell particles and their improved reactivity

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Abstract

Dilatation of aluminum (Al) core for micron-scale particles covered by alumina (Al{sub 2}O{sub 3}) shell was measured utilizing x-ray diffraction with synchrotron radiation for untreated particles and particles after annealing at 573 K and fast quenching at 0.46 K/s. Such a treatment led to the increase in flame rate for Al + CuO composite by 32% and is consistent with theoretical predictions based on the melt-dispersion mechanism of reaction for Al particles. Experimental results confirmed theoretical estimates and proved that the improvement of Al reactivity is due to internal stresses. This opens new ways of controlling particle reactivity through creating and monitoring internal stresses.

Authors:

McCollum, Jena; Pantoya, Michelle L. ^[1]; Tamura, Nobumichi ^[2]

Mechanical Engineering, Texas Tech University, Lubbock, Texas 79409 (United States)
Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

Publication Date:: Mon Sep 07 00:00:00 EDT 2015

OSTI Identifier:: 22494829

Resource Type:: Journal Article

Journal Name:: Journal of Applied Physics

Additional Journal Information:: Journal Volume: 118; Journal Issue: 9; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-8979

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; ALUMINIUM; ALUMINIUM OXIDES; ANNEALING; COPPER OXIDES; EXPERIMENT RESULTS; FLAMES; QUENCHING; REACTIVITY; STRESSES; SYNCHROTRON RADIATION; X-RAY DIFFRACTION

Citation Formats


                    Levitas, Valery I., E-mail: vlevitas@iastate.edu, McCollum, Jena, Pantoya, Michelle L., and Tamura, Nobumichi. Internal stresses in pre-stressed micron-scale aluminum core-shell particles and their improved reactivity.  United States: N. p., 2015. 
        Web.  doi:10.1063/1.4929642.

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                    Levitas, Valery I., E-mail: vlevitas@iastate.edu, McCollum, Jena, Pantoya, Michelle L., & Tamura, Nobumichi. Internal stresses in pre-stressed micron-scale aluminum core-shell particles and their improved reactivity.  United States.  https://doi.org/10.1063/1.4929642

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                    Levitas, Valery I., E-mail: vlevitas@iastate.edu, McCollum, Jena, Pantoya, Michelle L., and Tamura, Nobumichi. 2015.  
        "Internal stresses in pre-stressed micron-scale aluminum core-shell particles and their improved reactivity".  United States.  https://doi.org/10.1063/1.4929642.

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@article{osti_22494829,

  title        = {Internal stresses in pre-stressed micron-scale aluminum core-shell particles and their improved reactivity},

  author       = {Levitas, Valery I., E-mail: vlevitas@iastate.edu and McCollum, Jena and Pantoya, Michelle L. and Tamura, Nobumichi},

  abstractNote = {Dilatation of aluminum (Al) core for micron-scale particles covered by alumina (Al{sub 2}O{sub 3}) shell was measured utilizing x-ray diffraction with synchrotron radiation for untreated particles and particles after annealing at 573 K and fast quenching at 0.46 K/s. Such a treatment led to the increase in flame rate for Al + CuO composite by 32% and is consistent with theoretical predictions based on the melt-dispersion mechanism of reaction for Al particles. Experimental results confirmed theoretical estimates and proved that the improvement of Al reactivity is due to internal stresses. This opens new ways of controlling particle reactivity through creating and monitoring internal stresses.},

  doi          = {10.1063/1.4929642},

  url          = {https://www.osti.gov/biblio/22494829},
  journal      = {Journal of Applied Physics},

  issn         = {0021-8979},

  number       = 9,

  volume       = 118,

  place        = {United States},

  year         = {Mon Sep 07 00:00:00 EDT 2015},

  month        = {Mon Sep 07 00:00:00 EDT 2015}

}

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