Influence of 1 and 5 wt% TiC additions on the oxidation behaviour of pure tungsten

Proceedings of: 19th International Conference on Fusion Reactor Materials (ICFRM-19), 27 October-01 November 2019, La Jolla, California, U.S.AThe influence of 1 and 5 wt% of TiC nanoparticles on the oxidation behaviour of reinforced tungsten has been evaluated up to 700 °C in dry air. Isothermal thermogravimetric tests prove that the addition of 5 wt% of TiC particles is detrimental, increasing the mass gain of pure tungsten by a factor of ten. TiC particles act as stress concentrators, facilitating microcracking events within the scale and promoting decohesion between TiC-free boundaries and TiC-containing regions of the material. Compared to pure tungsten, lowering TiC addition to 1 wt% significantly improves the oxidation resistance at 700 °C by reducing about seven times the mass gain, while at 600 °C both materials exhibit similar resistance. At 700 °C, the presence of 1 wt% of TiC particles inhibits massive microcracking events occurring in the scale formed on pure tungsten, rendering the oxide scale denser and more protective.This research has been supported by the Regional Government of Madrid through TECHNOFUSIÓN(III)CM (S2018/EMT-4437) and the Ministerio de Economía y Competitividad of Spain (ENE2015-70300-C3-2-R MINECO/FEDER) and programs. The authors acknowledge the expert support of A. García and A. Tomás from the CENIM Microscopy Laboratory