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The interaction between cracks and inclusions plays an important role in the fracture behavior of particulate composites. It is commonly recognized that an inclusion stiffer than the matrix tends to deflect an approaching crack away while a softer inclusion attracts the crack. Here, we demonstrate by analytical modeling and numerical simulations that the crack-inclusion interaction can be tuned by an applied T-stress. Under a sufficiently large compressive applied T-stress, cracks can be attracted to stiffer inclusions while repelled by softer ones, thus reversing the conventional trend. Potential applications of this work include composite electrodes in lithium-ion batteries and hydraulic fracturing.
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This content will become publicly available on January 1, 2027
In-Situ Internal Deformation Measurement of an IDOX Particulate Estane Binder Composite via Backward Digital Volume Correlation
Background Digital volume correlation (DVC) of in-situ X-ray micro-computed tomography (μCT) images provides a powerful means to quantify internal deformation and damage characteristics of particulate composite materials under mechanical loading. However, accurately tracking structural evolution becomes more challenging when the material undergoes large deformations accompanied by crack formation and growth. Objective This study aims to improve the accuracy and robustness ofDVCanalysis in heavily damaged particulate composites by implementing a backward incremental DVC approach. Methods The internal response of a mock plastic-bonded explosive (PBX) composite was examined. The composite was fabricated by embedding IDOX crystals, 75–150 μm in size, within a polyurethane-based binder, Estane. A cylindrical specimen was subjected to unconfined compression, during which sequential μCT scans were acquired. In the backward DVC approach, correlations are performed in reverse, from the most deformed state back to the undeformed configuration through intermediate steps, using the conventional DVC framework. This method enhances displacement tracking fidelity in regions with severe cracking and interfacial failure. Results The backward incremental DVC approach provides improved resolution of displacement and deformation fields near crack-affected regions compared with conventional DVC methods. It enables detailed observation of interface delamination between grains and binder associated with crack initiation and coalescence. Conclusion The results demonstrate that the backward incremental DVC technique effectively characterizes complex deformation mechanisms in damaged particulate composites and provides valuable experimental data for validating high-fidelity numerical simulations that resolve grain-scale interactions.
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- PAR ID:
- 10667885
- Editor(s):
- Wang, Junlan
- Publisher / Repository:
- Springer Nature
- Date Published:
- Journal Name:
- Experimental Mechanics
- Volume:
- 66
- Issue:
- 1
- ISSN:
- 0014-4851
- Page Range / eLocation ID:
- 103 to 119
- Subject(s) / Keyword(s):
- IDOX/Estane particulate composite micro-Computed tomography Backward incremental digital volume correlation Internal Deformation.
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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