|Images of a self-healing test specimen with red dyed microencapsulated healing agent embedded in the epoxy matrix.
- Virgin sample.
- Cracks form in the matrix wherever damage occurs. A crack ruptures the microcapsules, releasing the healing agent into the crack plane through capillary action.
- The two halves of the specimen after it has been fractured into two pieces.
- On the crack faces, red healing agent is released from ruptured urea-formaldehyde microcapsules embedded in the epoxy.