Pulsed electric current sintering of tungsten composites for use as divertor target in a fusion reactor

Tungsten is selected as plasma-facing material in the divertor of the ITER fusion reactor. However, the mechanical properties of commercially available tungsten are not yet adequate for this application. Grain refinement is needed to improve the strength, ductility and other properties. With regard to the operating temperature, the recrystallization temperature must also be increased. To accomplish this, grain growth inhibitors such as yttrium oxide or titanium carbide are added and the powders are mechanically alloyed with tantalum (Ta) or rhenium (Re). Hot isostatic pressing is being used most often as sintering technique in order to produce high-density fine-grained tungsten from these powder mixtures. In this master's thesis, the potential of pulsed electric current sintering (PECS) is investigated as a viable alternative to produce these novel tungsten composites.