SPS Fabrication of Tungsten and Tungsten Rhenium Alloys in Support of NTR Fuels Development
Tungsten metal slugs were fabricated via Spark Plasma Sintering (SPS) of powdered metals at temperatures ranging from 1575 K to 1975 K and hold times of 5 minutes to 30 minutes, using powders with an average diameter of 7.8 µm. Sintered tungsten specimens were found to have relative densities ranging from 83% to 94% of the theoretical density for tungsten. Consolidated specimens were also tested for their Vickers Hardness Number (VHN), which were plotted as a function of relative density. Concurrently, tungsten and rhenium powders with average respective diameters of 0.5 µm and 13.3 µm were pre-processed either by High-Energy-Ball-Milling (HEBM) or by homogeneous mixing to yield W-25at.%Re mixtures. The powder batches were sintered at temperatures of 1975 K and 2175 K for hold times up to 60 minutes yielding relative densities in the range 94% to 97%. The combination of HEBM and sintering showed a significant decrease in the intermetallic phases compared to that of the homogenous mixing and sintering.
Webb, Jonathan A.; Charit, Indrajit; Sparks, Cory; Butt, Darryl P.; Frary, Megan; and Carroll, Mark. (2011). "SPS Fabrication of Tungsten and Tungsten Rhenium Alloys in Support of NTR Fuels Development". Nuclear and Emerging Technologies for Space 2011, NETS-2011, February 7-February 10, 2011, Albuquerque, NM, .