New progress in research on self-repairing man-made materials

To imitate the self-healing process of biological bones, the researchers introduced a channel system into fiber-reinforced polymer composites, and repaired damaged parts by injecting resin. The compressive strength of the repaired composite can reach 97% before damage.

The body of the European jet fighter is mainly composed of fiber reinforced polymer composites. This material is lighter in weight than the equivalent metal material, has higher strength and hardness, but is less plastic. Fiber reinforcement is essentially a planar mechanism that does not absorb and release well for the impacts it receives. As an aircraft panel, subtle impact damage is very difficult to detect, but it has an important impact on the mechanical properties of the material.

Dr. Richard Trask from the University of Bristol and colleagues tried to solve this problem by making the material self-repairing. Our body's bones are also composite materials composed of layered brittle cells. However, when there is a crack in the bone, it can be reconstructed by two kinds of bone cells: osteoclasts and osteoblasts. Erosion can erode bones and they create channels or channels in dead bones. Vascular vessels bring these osteoblasts to the site of injury through these tubes and slowly generate new bones.

The researchers introduced a piping system into a polymer composite by a "lost wax" method. If the material is damaged, a repair resin can be injected into these pipes to repair the damage. Experiments have found that the compressive strength of the repaired composite can reach 97% before damage.

The research on the self-repairing of man-made materials is of great significance to the development of related engineering fields.