Composite That Heals Itself 1,000 Times May Extend Spacecraft Lifetimes

North Carolina State University researchers developed a modified fiber‑reinforced polymer that uses 3D‑printed EMAA and embedded heaters to re-bond layers, and lab samples were intentionally broken and repaired more than 1,000 times; the university has licensed the technology to a startup, Structeryx Inc.

Researchers at North Carolina State University have reported a modified fiber‑reinforced polymer (FRP) that can repair layer separation when warmed. The design combines 3D‑printed EMAA thermoplastic applied to FRP layers with embedded carbon‑based heaters that heat the polymer so it flows into cracks and re-bonds layers. The team ran repeated laboratory cycles of deliberate damage and repair over 40 days. The university has licensed the work and a startup, Structeryx Inc., was formed to pursue applications. Key findings: - The composite integrates EMAA printed onto FRP layers and carbon‑based heaters embedded within the laminate. - Applying an electric current warms the EMAA, allowing it to flow into delamination cracks and re‑bond the layers. - In lab tests the team broke and repaired samples over 1,000 times across 40 days, with strength remaining above that of typical composites for roughly the first 500 cycles. - Over many cycles, accumulated fiber debris reduced strength somewhat, though repaired samples still outperformed delaminated composites. - The university has licensed the technology and Structeryx Inc. was created to work with partners on potential use cases. Summary: The approach is intended to allow repeated structural repairs using electrical power, which could be relevant to long‑lived FRP applications such as wind turbine blades and spacecraft components; potential trade‑offs noted by the researchers include added weight and increased cost. The university has licensed the technology and the startup is seeking partners to explore real‑world uses. Wider adoption and long‑term field performance remain to be determined.