This study discusses the formation of phases during sintering of tungsten by the FAST. Scanning electron microscopy, X-ray diffraction and transmission electron microscopy were revealed the in-situ formation of tungsten oxide and a formation of tungsten carbide shell around tungsten core. Tungsten carbide-rich shell is formed due to the carbon diffusion from the graphite die used in the FAST into tungsten at high temperatures. In contrast to easy removal of tungsten carbide shell by mechanical grinding, the formation of tungsten oxide in the W-matrix can influence the performance of such material when used as plasma-facing material in the fusion reactor. High-temperature experiments at 1873?K showed that tungsten-oxide phase starts to decompose, which results in material degradation and formation of voids and surface blisters.
COBISS.SI-ID: 31225127