Computational Frameworks for the Development and Qualification of Additive Manufacturing-Tailored Wire Feedstock for Naval Directed Energy Deposition

STTR topic DON27TZ02-NV013 (U.S. Department of Defense – Navy), Phase I and II. Open to U.S. small businesses; STTR projects partner with a U.S. research institution. Opens: December 2, 2026. Closes: January 6, 2027. As the Department of the Navy prepares for contested logistics environments, the ability to manufacture large, mission-critical replacement parts at the point of need has become a strategic imperative. Wire-fed DED is uniquely suited to this role: it operates safely with reactive metal alloys, achieves high deposition rates for large structural volumes, and is robust enough for shipboard and expeditionary deployment. Despite this operational advantage, a persistent and quantifiable performance gap prevents wire DED parts from meeting Navy structural qualification standards without extensive post-processing. The root cause of this gap is a thermal physics and geometric mismatch. Additive manufacturing (AM) processes span approximately five orders of magnitude in solidification cooling rate, which is the master variable governing grain size, phase selection, and precipitate morphology. Current wire feedstock is manufactured to welding wire specifications, engineered for arc welding thermal histories rather than the specific precision and cooling rates of robotic DED. The consequences are well-documented: • Microstructural Deficits: Precipitation-strengthened aluminum alloys exhibit a 40-70% yield strength reduction in DED compared to laser powder bed fusion, driven by insufficient cooling rates to nucleate strengthening dispersoids. Titanium alloys (e.g., Ti-6Al-4V) develop continuous grain boundary alpha films that degrade ductility and fatigue life. • Residual Stress Instability: Residual stresses retained from the wire drawing process cause wire tip instability (cast/helix) in the DED melt zone, producing porosity and build failures. • Geometric and Surface Topography: Macroscopic inconsistencies in wire diameter dictate volumetric feed-rate…