Duration: 12 months
The project targets a long-standing reliability challenge in space structures: fatigue damage accumulating under thermal and mechanical cycling that is difficult to repair in orbit. We propose and validate a self-healing aluminum metal matrix composite (Al6061) manufactured by Directed Energy Deposition (DED), in which low melting tin–bismuth (Sn–Bi) particles act as healing agents. A dual coating protects the particles during DED and enables repeatable activation. Gentle heating (~140 °C) melts the Sn–Bi phase so it flows into microcracks and re-solidifies, thereby restoring stiffness and slowing or arresting crack growth. Over 12 months at TU Darmstadt, we will develop powders and coatings, optimize the DED process window, and conduct microstructural and chemical analyses (SEM/TEM, EDS, XRD) alongside comprehensive mechanical testing under static and cyclic loads. The study quantifies healing efficiency as recovery of stiffness, strength and toughness after controlled activation, and measures fatigue endurance and crack-growth behavior before and after healing.
Expected outcomes include validated healing performance and design guidelines (capsule fraction, coating architecture, activation protocol) for space-relevant components with higher reliability and reduced maintenance.
