Impact of Ceramic Nanoparticle Additions on the Properties of Additive Manufactured Refractory Metals

Refractory metals and alloys are of major interest for nuclear fusion systems, space nuclear power and propulsion, and hypersonic applications due to their desirable properties at elevated temperatures (>1500°C). Limitations of refractory materials include their low ductility, poor oxidation resistance, and high manufacture cost using traditional techniques. Additive manufacturing (AM) can reduce material waste associated with manufacture, but AM fabrication is impacted by the brittleness of these refractory metals, resulting in excessive cracking during printing. To address this concern, nanoparticles can be incorporated into AM powder to reduce cracking and improve mechanical properties. This work focuses on the impact on printability and material properties of adding different ceramic nanoparticles to refractory metals. Results will be shown for the as-built, stress-relieved, and hot isostatic pressed conditions of these ceramic dispersion strengthened refractory metals (tungsten and molybdenum). These results will be discussed and compared with the results obtained for the pure metal.