The Tungsten-Based Plasma-Facing Materials

Abstract

The plasma-facing materials in fusion reactors will face very extreme servicing condition such as high temperatures, high thermal loads, extreme irradiation conditions induced by high-energy neutron, and high fluences of high-flux and low-energy plasma. Tungsten is considered as the most promising material for plasma-facing components (PFCs) in the magnetic confinement fusion devices, due to its high melting temperature, high thermal conductivity, low swelling, low tritium retention, and low sputtering yield. However, some important shortcomings such as the irradiation brittleness and high ductility-brittle transition temperature of pure tungsten limit its application. Focusing on this issue, various W alloys with enhanced performance have been developed. Among them, nanoparticle dispersion strengthening such as oxide particle dispersion-strengthened (ODS-W) and carbide particle dispersion-strengthened (CDS-W) tungsten alloys and W fiber-reinforced W f /W composites are promising. This chapter mainly reviews the preparation, microstructure, properties, regulation, and service performance evaluation of ODS-W, CDS-W, and W f /W materials, as well as future possible development is proposed.

Progress and Challenges of Additive Manufacturing of Tungsten and Alloys as Plasma-Facing Materials

“…Nuclear fusion presents an extremely hostile environment subject to exposure of severe thermal loads, high-neutron-energy bombardments, and neutron fluences. The tokamak reactor reports ≥1026 n/m 2 when operating in a steady state, at high fluxes, and under low-energy hydrogen (H) and helium (He) plasma irradiations [1][2][3][4]. Such aspects impose significant restrictions on the design of plasma-facing components (PFCs) and plasmafacing materials (PFMs).…”

“…Such aspects impose significant restrictions on the design of plasma-facing components (PFCs) and plasmafacing materials (PFMs). Therefore, improving the peak conditions of PFMs increases the performance of PFCs, enabling more freedom in future fusion reactors [1,5]. To address the technical challenges in PFMs for fusion devices, materials must be capable of operating in a fusion reactor environment for an extended time while maintaining those desirable traits.…”

“…Tungsten (W) and W alloys have excited increased interest as a potential PFM candidate for enduring such extreme conditions [1,6]. W is noteworthy as a potential PFM for both the International Thermonuclear Experimental Reactor (ITER) and the demonstration power plant (DEMO), proposed for divertor applications [7].…”

High Densification of Tungsten via Hot Pressing at 1300 °C in Carbon Presence

“…In many respects, tungsten is one of the best potential candidates for first-wall applications and plasma-facing surfaces. Tungsten produces a relatively low amount of plasma impurities and has a low ion sputtering yield [ 2 ]. The crucial issue hampering tungsten use is its brittleness [ 3 ].…”