Damage Tolerant Mechanisms of Natural Biomaterials for Design of Novel Engineered Bio-Inspired Composites

Abstract

This one-year grant is complete and the final report received. This project was built on research undertaken by the Brown group at the University of Cambridge that involved understanding how soft biological materials respond to mechanical damage. This work required the development of experimental techniques different than the ones typically used for hard synthetic materials. The key focus of this project was the retrofitting of a split-Hopkinson pressure bar for use with soft materials. The Tensile Hopkinson Bar system has been entirely retrofitted to an easier-to-use, more modular configuration. The gas gun now sits on a steel rail system to which multiple ring mounts can be clamped. The mobility of the mounts facilitates testing of samples with a wide range of geometries with varied gripping methods. Tests with plastics including polyethylene were conducted. Due to attendant changes in the opacity of the samples under testing, these experiments were visualized with high-speed videography to assess changes to the strain states of the samples, which can be coupled to information from the strain gauges present on the bars. Signals from the samples could be detected and differentiated from artefacts caused by the grips. A follow-on grant (FA9550-19-1-7006) was awarded to continue the work.

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Document Details

Document Type
Technical Report
Publication Date
Apr 30, 2020
Accession Number
AD1106352

Entities

People

  • Katherine A. Brown

Tags

Communities of Interest

  • Engineered Resilient Systems
  • Space

DTIC Thesaurus Topics

  • Air Force
  • Air Force Research Laboratories
  • Biomaterials
  • Blast
  • Blast Injuries
  • Composite Materials
  • Compression
  • Correlation Techniques
  • Engineering
  • Gas Guns
  • Materials
  • Materials Laboratories
  • Mechanical Properties
  • Mechanics
  • Plastics
  • Synthetic Materials
  • Universities

Readers

  • Computer Vision.
  • Mechanical Engineering/Mechanics of Materials.
  • Software Engineering