Fragmentation as an aggregation process: the role of defects.

Area of Science:

• Physics
• Materials Science
• Soft Matter Physics

Background:

• Cohesive objects fragment under strong deformation, such as during impacts.
• Previous work demonstrated fragmentation via an inverse aggregation cascade in magnetized spheres.

Purpose of the Study:

• To investigate fragmentation dynamics in a 1D cohesive material with modified force laws.
• To explore the influence of defects and force distribution on fragmentation.
• To understand the role of capillary bridges in cohesive fragmentation.

Main Methods:

• Utilizing hydrogel beads linked by capillary bridges to model cohesive interactions.
• Inducing sudden expansion to observe fragmentation.
• Analyzing the cascade of aggregations and its interruption points.

Main Results:

• Fragmentation still occurs through a cascade of aggregations.
• Increased force disorder and defects in cohesion lead to earlier interruption of the aggregation cascade.
• The nature of the force law between beads influences fragmentation patterns.

Conclusions:

• The fragmentation of 1D cohesive materials is sensitive to the details of inter-particle forces and defects.
• Force disorder plays a critical role in modifying fragmentation dynamics.
• This study provides insights into the failure mechanisms of cohesive structures.