ORNL Additive Manufacturing “Mighty Mo”

ORNL researchers used Electron Beam Powder Bed Fusion to produce crack-free molybdenum, proving its viability for Additive Manufacturing. (Courtesy of ORNL/US Dept of Energy)

Oak Ridge National Laboratory, Oak Ridge, Tennessee, proved molybdenum titanium carbide, a refractory metal alloy that can withstand extreme temperature environments, can also be crack free and dense when produced with electron beam powder bed fusion. Molybdenum (Mo) and other refractory alloys are difficult to process through traditional manufacturing because of their high melting temperature, reactivity with oxygen and brittleness.

To address these challenges, the ORNL team formed a Mo metal matrix composite (MMC) by mixing molybdenum and titanium carbide powders, melt the mixture with an electron beam, and control the cooling rate to optimize performance.

“Our results showed that fabrication from a mechanically alloyed MMC powder is feasible,” ORNL’s Mike Kirka said. “The structures formed by the fused powders can withstand high temperatures, indicating that molybdenum and its alloys can be used for aerospace and energy conversion applications.”