Small cracks that develop within the fiberglass bodies of modern cars and planes can quickly turn into irreversible damage, which undermines their structural integrity. Unfortunately, the materials used to construct these vehicles, called fiber-reinforced composites, are challenging to repair using conventional methods.
A new system developed by researchers at the Beckman Institute at the University of Illinois at Urbana-Champaign embeds a 3D vascularized network within the composite, akin to the way blood vessels embed tissue in the human body. This network enables these composites to repair themselves automatically when the material is damaged.
“When a fracture occurs, this ruptures the separate networks of healing agents, automatically releasing them into the crack plane — akin to a bleeding cut,” said Jason Patrick, a Ph.D. candidate in civil engineering and lead author on the paper. “As they come into contact with one another in situ, or within the material, they polymerize to essentially form a structural glue in the damage zone.”
After testing over multiple cycles, the researchers report that cracks healed successfully with nearly 100 percent efficiency. “The beauty of this self-healing approach is, we don’t have to probe the structure and say, this is where the damage occurred and then repair it ourselves,” said Patrick.
Nancy Sottos, materials science and engineering professor and co-corresponding author, added, “Creating the vasculature integrates seamlessly with typical manufacturing processes of polymer composites, making it a strong candidate for commercial use.”
Read more at the Beckman Institute: Repeated self-healing now possible in composite materials
[images: Beckman Institute, flickr/Morgan]