Gelcasting low-carbon B4C for cermets (Allison intern SULI paper)

doi:https://doi.org/10.2172/1474333

Title: Gelcasting low-carbon B4C for cermets (Allison intern SULI paper)

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Abstract

A boron carbide (B ₄C) gelcasting suspension involving melamine formaldehyde (MF) resin was developed to obtain green bodies with low carbon after pyrolysis. MF resin allows highly complicated B ₄C parts to be produced with little to no shrinkage when gelcast into molds. A MF binder content of ~7.5 wt % consistently produced green bodies with sufficient strength to withstand demolding and handling. Variations in B ₄C particle size, curing temperature, and pH were investigated in order to optimize the suspension for casting. Resin pyrolysis trials showed that 90.0 ± 0.9 wt % of resin mass was lost during pyrolysis, corresponding to < 1 wt % of binder residual in the overall green bodies. The minimal carbon content in the green bodies is favorable for the infiltration of aluminum into open pore spaces. Due to the high hardness of B ₄C and the ductility of aluminum, the ceramic-metal (cermet) composite formed is ideal for applications such as light-weight armors.

Authors:

Pearson, Allison ^[1]; Lu, Ryan ^[2]; DuFrane, Wyatt ^[2]; Landingham, Richard ^[2]; Kuntz, Joshua ^[2]

Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Functional Materials Synthesis Group; Univ. of California, Berkeley, CA (United States)
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Functional Materials Synthesis Group

Publication Date:: 2018-08-16

Research Org.:: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

Sponsoring Org.:: USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:: 1474333

Report Number(s):: LLNL-TR-756666
944093

DOE Contract Number:: AC52-07NA27344

Resource Type:: Technical Report

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE; 42 ENGINEERING

Citation Formats


                    Pearson, Allison, Lu, Ryan, DuFrane, Wyatt, Landingham, Richard, and Kuntz, Joshua. Gelcasting low-carbon B4C for cermets (Allison intern SULI paper).  United States: N. p., 2018. 
        Web.  doi:10.2172/1474333.

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                    Pearson, Allison, Lu, Ryan, DuFrane, Wyatt, Landingham, Richard, & Kuntz, Joshua. Gelcasting low-carbon B4C for cermets (Allison intern SULI paper).  United States.  https://doi.org/10.2172/1474333

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                    Pearson, Allison, Lu, Ryan, DuFrane, Wyatt, Landingham, Richard, and Kuntz, Joshua. Thu .  
        "Gelcasting low-carbon B4C for cermets (Allison intern SULI paper)".  United States.  https://doi.org/10.2172/1474333.  https://www.osti.gov/servlets/purl/1474333.

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@article{osti_1474333,

  title        = {Gelcasting low-carbon B4C for cermets (Allison intern SULI paper)},

  author       = {Pearson, Allison and Lu, Ryan and DuFrane, Wyatt and Landingham, Richard and Kuntz, Joshua},

  abstractNote = {A boron carbide (B4C) gelcasting suspension involving melamine formaldehyde (MF) resin was developed to obtain green bodies with low carbon after pyrolysis. MF resin allows highly complicated B4C parts to be produced with little to no shrinkage when gelcast into molds. A MF binder content of ~7.5 wt % consistently produced green bodies with sufficient strength to withstand demolding and handling. Variations in B4C particle size, curing temperature, and pH were investigated in order to optimize the suspension for casting. Resin pyrolysis trials showed that 90.0 ± 0.9 wt % of resin mass was lost during pyrolysis, corresponding to < 1 wt % of binder residual in the overall green bodies. The minimal carbon content in the green bodies is favorable for the infiltration of aluminum into open pore spaces. Due to the high hardness of B4C and the ductility of aluminum, the ceramic-metal (cermet) composite formed is ideal for applications such as light-weight armors.},

  doi          = {10.2172/1474333},

  url          = {https://www.osti.gov/biblio/1474333},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {2018},

  month        = {8}

}

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https://doi.org/10.2172/1474333

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