Tantalum and molybdenum barriers to prevent carbon diffusion in spark plasma sintered tungsten

Carbide reduces the ductility of tungsten and leads to brittle intergranular fractures. These fractures are inevitably formed in tungsten by carbon diffusion owing to graphite mold during spark plasma sintering. Here, we introduce protective foils made up of two different carbide-forming elements, molybdenum and tantalum, to minimize the carbide formation. Cross-sectional elemental mapping shows that the tantalum foil suppresses carbon diffusion...