Direct observation and image-based simulation of three-dimensional tortuous crack evolution inside opaque materials.

Area of Science:

• Materials Science
• Fracture Mechanics
• Solid Mechanics

Background:

• Understanding complex crack geometries and propagation is crucial for material integrity.
• Heterogeneous materials present unique challenges due to internal structural variations.
• Existing methodologies may not fully capture the 3D nature of tortuous cracks.

Purpose of the Study:

• To develop and present a novel combined methodology for analyzing 3D tortuous crack geometry.
• To identify key features influencing crack propagation in heterogeneous materials.
• To explain unexpected damage phenomena and varied crack growth rates.

Main Methods:

• A novel combined methodology was developed to study crack geometry and propagation.
• The approach allowed for the identification of hidden crack segments.
• Analysis focused on crack-tip fields and plastic zone behavior within heterogeneous materials.

Main Results:

• Unexpected severe damage events were linked to unseen crack segments shifting the plastic zone.
• Varied crack growth rates along the crack front were attributed to reduced crack-tip fields from neighboring hidden cracks.
• The methodology successfully identified and characterized complex 3D crack features.

Conclusions:

• The proposed methodology offers a powerful new approach to studying fracture mechanisms.
• Hidden crack segments significantly influence material damage and crack propagation behavior.
• This work provides deeper insights into crack dynamics in heterogeneous materials.