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Defect-mediated stripe reordering in wrinkles upon gradual changes in compression direction
Takuya Ohzono1, Masatsugu Shimomura
1Dissipative-Hierarchy Structures Laboratory, Frontier Research System, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
Summary
Microwrinkles exhibit stripe rearrangements under changing compression. Local stripe orientation shifts suddenly due to nearby dislocation gliding, revealing organized motion and dislocation interactions.
Area of Science:
- Materials Science
- Physics of soft matter
Background:
- Microwrinkles are patterned surfaces formed by compression.
- Understanding stripe rearrangements is crucial for predicting material behavior.
Purpose of the Study:
- To investigate stripe rearrangements in microwrinkles under changing compression direction.
- To analyze the relationship between stripe orientation and dislocation motion.
Main Methods:
- Subjecting microwrinkles to gradual changes in compression direction.
- Observing stripe orientation using microscopy.
- Analyzing dislocation gliding events.
Main Results:
- Spatially averaged stripe orientation closely follows compression direction (3-4 degree deviation).
- Local stripe orientation remains stable until a nearby dislocation glide causes sudden reorientation.
- Organized dislocation glide motions lead to transient, regular patterns in stripe orientation.
Conclusions:
- Dislocation interactions play a significant role in stripe rearrangements.
- The observed phenomena provide insights into the collective behavior of dislocations in patterned surfaces.
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