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09:12
A Method for Studying the Temperature Dependence of Dynamic Fracture and Fragmentation
Published on: June 28, 2015
Dynamics of fracture in drying suspensions
E R Dufresne1, D J Stark, N A Greenblatt
1DEAS, Department of Physics, and Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA. eric.dufresne@yale.edu
Langmuir : the ACS Journal of Surfaces and Colloids
|August 9, 2006
Summary
Drying colloidal silica films crack due to water loss, forming an elastic network. Crack motion arises from particle network aging and arrested crack tip deformation.
Area of Science:
- Materials Science
- Fluid Dynamics
- Soft Matter Physics
Background:
- Drying of colloidal dispersions leads to significant volumetric strain.
- This strain can induce fracture in the forming solid films.
- Understanding fracture dynamics is crucial for controlling material properties.
Purpose of the Study:
- To investigate the dynamics of fracture in drying colloidal silica films.
- To elucidate the mechanisms driving crack initiation and propagation.
- To establish a physical model for crack evolution during drying.
Main Methods:
- Experimental observation of crack dynamics in drying silica films.
- Analysis of crack intermittency and motion.
- Theoretical modeling based on energy balance principles.
Main Results:
- Fracture occurs via cracking as the nanoparticle dispersion dries and forms an elastic network.
- Crack dynamics are characterized by intermittent motion, influenced by arrested crack tips and network aging.
- A universal evolution of single crack dynamics is observed, governed by elastic power, interfacial energy, and viscous dissipation.
Conclusions:
- The study reveals the complex interplay of elastic, interfacial, and viscous forces in governing fracture during colloidal film drying.
- The findings provide insights into the aging and deformation mechanisms of the elastic nanoparticle network.
- A universal model is proposed for crack dynamics, applicable to drying colloidal systems.
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