Faceted wrinkling by contracting a curved boundary

Area of Science:

• Mechanics of Materials
• Materials Science
• Applied Physics

Background:

• Single-mode deformations in 2D materials are crucial for deployable structures.
• Existing methods, like the Miura-ori fold, often require extensive pre-patterning.
• Robustness and efficiency in material deformation are key design considerations.

Purpose of the Study:

• To investigate wrinkle pattern formation in 2D materials subjected to inward boundary contraction.
• To explore a novel method for achieving single-mode-like deformations with minimal pre-patterning.
• To analyze the structural characteristics and energy landscape of the resulting wrinkle patterns.

Main Methods:

• Utilized finite-element analysis to simulate the contraction of a thin circular annular sheet.
• Modeled the resulting wrinkle structure as an isometric configuration of conical sectors and triangular facets.
• Analyzed the energy associated with bending and stretching during deformation.

Main Results:

• Inward contraction of a curved boundary generates a fine, novel wrinkle pattern.
• The observed pattern is well-approximated by an isometric structure.
• Deformation is restricted to a low-bending energy channel, minimizing stretching.
• This process achieves single-mode characteristics with significantly reduced pre-patterning.

Conclusions:

• Boundary-induced buckling offers a new approach to control sheet morphology.
• This method provides a robust and energy-efficient pathway for creating complex 2D material structures.
• Minimal pre-patterning makes this technique highly applicable for deployable structures.