Dimension-controlled formation of crease patterns on soft solids

Area of Science:

• Materials Science
• Mechanics of Materials
• Soft Matter Physics

Background:

• Soft solids like silicone and PDMS are crucial for flexible electronics and medical engineering.
• Controlling surface morphology of soft solids opens new application avenues.
• Mechanical loading-induced elastic instability offers a facile method for surface pattern control.

Purpose of the Study:

• To investigate the control of surface morphology in soft solids via mechanical loading.
• To experimentally measure critical strain for crease nucleation under plane strain conditions.
• To understand the transition of creasing patterns in silicone under compressive loading.

Main Methods:

• Experimental measurement of critical strain for crease nucleation.
• Application of compressive loading to silicone specimens.
• Finite element simulations to analyze creasing mechanisms.

Main Results:

• Experimental results for critical strain align with nonlinear large deformation theory.
• Silicone exhibits a transition in creasing patterns (single/double channeling to unchanneling) based on specimen dimensions.
• Established a relationship between crease depth and spacing, validated by simulations and experiments.

Conclusions:

• Elastic instability provides effective control over soft solid surface morphology.
• Compressive loading and specimen geometry dictate silicone creasing patterns.
• Finite element analysis accurately models creasing phenomena in soft solids.