Non-Newtonian Fabric-Fluid Composites: Fabrication, Characterization and Testing for Anti-Ballistics Applications

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Non-Newtonian Fabric-Fluid Composites: Fabrication, Characterization and Testing for Anti-Ballistics Applications Clemson University TigerPrints All Theses Theses 4-2018 Non-Newtonian Fabric-Fluid Composites: Fabrication, Characterization and Testing for Anti-Ballistics Applications Hayley M. Weir Clemson University Follow this and additional works at: https://tigerprints.clemson.edu/all_theses Part of the Materials Science and Engineering Commons Recommended Citation Weir, Hayley M., "Non-Newtonian Fabric-Fluid Composites: Fabrication, Characterization and Testing for Anti-Ballistics Applications" (2018). All Theses. 3258. https://tigerprints.clemson.edu/all_theses/3258 This Thesis is brought to you for free and open access by the Theses at TigerPrints. It has been accepted for inclusion in All Theses by an authorized administrator of TigerPrints. For more information, please contact [email protected]. NON-NEWTONIAN FABRIC-FLUID COMPOSITES: FABRICATION, CHARACTERIZATION AND TESTING FOR ANTI-BALLISTICS APPLICATIONS A Thesis Presented to the Graduate School of Clemson University In Partial Fulfillment of the Requirements for the Degree Master of Science Materials Science and Engineering by Hayley M. Weir April 2018 Accepted by Dr. Igor Luzinov, Committee Chair Dr. Konstantin Kornev, Committee Co-Chair Dr. Phillip Brown Dr. Ryan Burke Abstract This thesis aims to characterize non-Newtonian suspensions for anti-ballistics applications. This involves characterizing the rheological behavior of each suspension. It also includes characterizing the interactions of the suspensions with several types of fabrics with known anti- ballistics properties. The study also tests the armor composites under ballistics stresses by firing on them with standardized military weaponry. This data is then compiled to determine which, if any, of the fabrics and suspensions are ultimately suitable for anti-ballistics uses. ii Acknowledgements This research was conducted with the help of the US Air Force Academy and the Department of Defense Center of Innovation. Without their aid, this research would have never achieved success. The USAFA Combat Arms Training and Maintenance unit was invaluable for their flexibility and willingness to let us travel and use their shooting ranges for our testing. At Clemson, there are too many people to thank individually, but I would like to thank my committee members, Dr. K. Kornev, Dr. I. Luzinov, Dr. P. Brown, and Dr. R. Burke. Your expertise has been invaluable. I’d also like to thank my group members. Erik, Emma, Mastooreh, Charles, you all made this work fun and stress free, and I knew if I had problems with any part of the work I could always ask you. Thank you. iii Table of Contents Abstract ............................................................................................................................................ i Acknowledgements ....................................................................................................................... iii Table of Contents ........................................................................................................................... iv List of Figures .............................................................................................................................. vii List of Tables ................................................................................................................................ xii Introduction .................................................................................................................................... 1 References .................................................................................................................................... 2 2. Literature Review ....................................................................................................................... 4 2.1 Parameters of Non-Newtonian Suspensions ........................................................................... 4 2.2 Behaviors of Suspensions ....................................................................................................... 5 2.2.1 Particle Type ................................................................................................................... 6 2.2.2 Particle Size ..................................................................................................................... 6 2.2.3 Volume Fraction of Solids .............................................................................................. 8 2.2.4 Particle Interactions with the Suspending Medium ......................................................... 9 2.2.5 Additives to the Suspensions ......................................................................................... 10 2.2.6 Type and Molecular Weight of the Suspending Medium.............................................. 12 2.2.7 Other Considerations ..................................................................................................... 14 2.2.8 Conclusions ................................................................................................................... 14 2.3 Suspension-Fabric Interactions............................................................................................. 15 2.3.1 Effect of Suspensions on Inter-Fiber Friction ............................................................... 15 iv 2.3.2 Effect of Suspensions on Amount of Fabric Used ........................................................ 17 2.3.3 Effect of Suspensions on Various Fabrics ..................................................................... 17 2.3.4 Conclusions ................................................................................................................... 19 2.4 Performance Characteristics of Suspension-Fabric Composites .......................................... 20 2.4.1 Effects of Build Sequence ............................................................................................. 20 2.4.2 Flexibility Performance ................................................................................................. 22 2.4.3 Stab Resistance/Drop Tower Performance .................................................................... 22 2.4.4 Ballistic Impact Performance ........................................................................................ 24 2.4.5 Challenges and Considerations ..................................................................................... 25 2.4.6 Conclusions ................................................................................................................... 25 References .................................................................................................................................. 26 3. Characterization of Suspensions ............................................................................................. 32 3.1 Materials ............................................................................................................................... 32 3.2 Suspension Preparation ........................................................................................................ 32 3.3 Optical Imaging .................................................................................................................... 34 3.4 Rheology............................................................................................................................... 38 3.5 Surface Tension .................................................................................................................... 45 3.6 QCM-D ................................................................................................................................. 49 3.7 Conclusions .......................................................................................................................... 64 References .................................................................................................................................. 65 4. Characterization of Fluid-Fabric Interaction ........................................................................ 67 4.1 Materials ............................................................................................................................... 67 4.2 Composite Preparation ......................................................................................................... 67 v 4.3 Contact Angle ....................................................................................................................... 69 4.4 Pore Size Distribution ........................................................................................................... 72 4.5 Pressure Testing .................................................................................................................... 81 4.6 Tensile Testing ..................................................................................................................... 86 4.7 Conclusions .......................................................................................................................... 89 References .................................................................................................................................. 89 5. Ballistics Testing ....................................................................................................................... 91 5.1 Setup for Ballistics Testing................................................................................................... 91 5.2 Prototype Preparation ..........................................................................................................
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