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A Coupled Experiment-finite Element Modeling Methodology for Assessing High Strain Rate Mechanical Response of Soft Biomaterials
Published on: May 18, 2015
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Mixed mode crack propagation in staggered biocomposites using phase field modelling
1Birla Institute of Technology and Science, Pilani, Rajasthan, 333031, India.
Journal of the Mechanical Behavior of Biomedical Materials
|September 25, 2019
Summary
Natural composites exhibit remarkable fracture resistance due to staggered mineral platelets. This study reveals how mixed-mode loading influences crack propagation and fracture mechanisms in these materials.
Area of Science:
- Materials Science
- Mechanical Engineering
- Biomimetics
Background:
- Natural biocomposites display exceptional fracture resistance and strength.
- Staggered mineral platelets in an organic matrix, resembling a brick-and-mortar structure, are key to their mechanical properties.
- Existing models often assume Mode I fracture, neglecting mixed-mode effects.
Purpose of the Study:
- To investigate crack propagation in staggered composites under mixed-mode loading conditions.
- To understand how material properties and microstructure influence fracture behavior.
- To explore novel fracture mechanisms arising from mixed-mode deformation.
Main Methods:
- Utilized a phase field method to simulate crack propagation.
- Analyzed crack trajectories under varying elastic modulus mismatches, microstructure geometries, and mode mixity ratios.
- Applied maximum tangential stress and strain energy density criteria to analyze crack tip behavior.
Main Results:
- Identified four distinct crack trajectories dependent on elastic mismatch, microstructure, and mode mixity.
- Observed that high elastic modulus mismatch leads to crack propagation independent of mode mixity.
- Found that moderate mismatch and high mode mixity induce interface delamination.
Conclusions:
- Crack trajectory in staggered composites is highly sensitive to material properties and loading conditions.
- Mixed-mode loading introduces complex fracture mechanisms, including interface delamination.
- The findings provide insights into designing advanced composite materials with enhanced fracture toughness.
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