Molecular dynamics of shock loading of metals with defects

Belak, J F

Title: Molecular dynamics of shock loading of metals with defects

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Abstract

The finite rise time of shock waves in metals is commonly attributed to dissipative or viscous behavior of the metal. This viscous or plastic behavior is commonly attributed to the motion of defects such as dislocations. Despite this intuitive understanding, the experimental observation of defect motion or nucleation during shock loading has not been possible due to the short time scales involved. Molecular dynamics modeling with realistic interatomic potentials can provide some insight into defect motion during shock loading. However, until quite recently, the length scale required to accurately represent a metal with defects has been beyond the scope of even the most powerful supercomputers. Here, the author presents simulations of the shock response of single defects and indicate how simulation might provide some insight into the shock loading of metals.

Authors:

Belak, J F ^[1]

Lawrence Livermore National Lab., CA (United States)

Publication Date:: Wed Dec 31 00:00:00 EST 1997

Research Org.:: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Sponsoring Org.:: USDOE, Washington, DC (United States)

OSTI Identifier:: 332725

Report Number(s):: SAND-98-1591; CONF-9709141-PROC.
ON: DE99000778; TRN: IM9916%%27

DOE Contract Number:: W-7405-ENG-48

Resource Type:: Conference

Resource Relation:: Conference: 5. joint Russian-American computational mathematics conference, Albuquerque, NM (United States), 2-5 Sep 1997; Other Information: PBD: [1997]; Related Information: Is Part Of Proceedings of the 5. joint Russian-American computational mathematics conference; PB: 312 p.

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; 99 MATHEMATICS, COMPUTERS, INFORMATION SCIENCE, MANAGEMENT, LAW, MISCELLANEOUS; IMPACT SHOCK; SHOCK WAVES; CRYSTAL DEFECTS; PLASTICITY; MOLECULAR DYNAMICS METHOD; METALS; MATHEMATICAL MODELS

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                    Belak, J F. Molecular dynamics of shock loading of metals with defects.  United States: N. p., 1997. 
        Web.

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                    Belak, J F. Molecular dynamics of shock loading of metals with defects.  United States.

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                    Belak, J F. 1997.  
        "Molecular dynamics of shock loading of metals with defects".  United States.  https://www.osti.gov/servlets/purl/332725.

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@article{osti_332725,

  title        = {Molecular dynamics of shock loading of metals with defects},

  author       = {Belak, J F},

  abstractNote = {The finite rise time of shock waves in metals is commonly attributed to dissipative or viscous behavior of the metal. This viscous or plastic behavior is commonly attributed to the motion of defects such as dislocations. Despite this intuitive understanding, the experimental observation of defect motion or nucleation during shock loading has not been possible due to the short time scales involved. Molecular dynamics modeling with realistic interatomic potentials can provide some insight into defect motion during shock loading. However, until quite recently, the length scale required to accurately represent a metal with defects has been beyond the scope of even the most powerful supercomputers. Here, the author presents simulations of the shock response of single defects and indicate how simulation might provide some insight into the shock loading of metals.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/332725},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Wed Dec 31 00:00:00 EST 1997},

  month        = {Wed Dec 31 00:00:00 EST 1997}

}

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