R. Li, G. Álvarez, A. Ipakchi, L. Cupertino-Malheiros, M. R. Gilbert, E. Martínez-Pañeda, E. Prestat
Nuclear Materials and Energy
https://doi.org/10.1016/j.nme.2025.101988
Resumen
The oxidation of pure W and the sublimation of W oxide have been investigated to assess their impact on the
lifecycle of a fusion power plant. Pure W has been oxidised at temperatures between 400 and 1050 °C and for
durations ranging between 1 and 70 h. The formation of voids and cracks has been observed at temperatures
above 600 °C, leading to the formation of dust or oxide spalling, which could be problematic in maintenance
and waste-handling scenarios of a fusion power plant. Preferential oxidation taking place at the edge of the
specimen was characterised, and its impact is discussed in relation to component design. Characterisation using
electron microscopy and Raman spectroscopy revealed that the oxide scale is formed of three main layers: the
inner layer is 30-50 nm thick WO₂ oxide, the middle layer is a 10-20 μm of WO272 and the outer layer is
formed of WO2g/WO₂ phases – whose thickness varies according to the total thickness of the oxide scale.
The observed microstructure is discussed in relation to the parabolic-to-linear kinetics and its potential impact
on tritium permeation and detritiation efficiency.