The US Department of Energy (DOE) announced up to $30 million in funding to develop first-wall materials—the materials used for the chamber where fusion reactions occur—that can maintain design performance in a fusion power plant. (DE-FOA-0003240)

As fusion energy advances toward commercial deployment, finding materials capable of optimized performance for a fusion first wall presents a significant scientific and engineering opportunity. The Creating Hardened and Durable Fusion First-Wall Incorporating Centralized Knowledge (CHADWICK) program aims to support the development and production of these materials.

Managed by DOE’s Advanced Research Projects Agency-Energy (ARPA-E), the CHADWICK program will pursue discovery and testing of novel, first-wall materials that will maintain design performance over the target 40-year design lifetime of a fusion power plant.

In most fusion power systems, the fusion reactions are physically contained by the first wall. The first wall bears the mechanical load and protects the components from the extreme heat and highly energetic charged and neutral particles.

The safety and structural performance of the first wall are compromised over time by significant exposure to high-energy (>1 million electron volts (MeV)) neutrons and heat flux as much as 10 megawatts per square meter (MW/m²)). As fusion energy advances towards commercial deployment, the lifetime and maintainability of first-wall materials will become a major challenge for the commercial viability of fusion power plants with high neutron flux.

Conceptual illustration of a fusion power system from ITER and the layered components between the fusion plasma and the ambient environment. DE-FOA-0003240

In many envisioned fusion energy systems, the first wall faces extreme heat flux and is directly exposed to highly energetic charged and neutral particles. The safety and structural performance of the first wall are compromised over time by significant exposure to the extreme environment.

Projects funded through CHADWICK will go beyond optimization of known alloys and provide a comprehensive wide-ranging survey and analysis of new material chemistries and manufacturing processes by redefining what is possible in fusion materials.

The CHADWICK program comprises three technical categories to support the program objectives. Applicants can apply to Category A, Category B, a combination of Categories A and B, or Category C, based on their expertise.

• CATEGORY A – PLASMA-FACING COMPONENT MATERIALS: Applicants to this category will discover and validate materials that maintain room temperature ductility after significant irradiation damage and helium generation while satisfying the unirradiated thermal conductivity, plasma erosion, and tritium retention performance metrics of tungsten in fusion power system first-wall applications.

• CATEGORY B – STRUCTURAL MATERIALS: Applicants to this category will discover and validate materials that maintain room temperature ductility after significant irradiation damage and helium generation while satisfying the unirradiated thermal, mechanical, and tritium retention performance metrics of RAFM steels in fusion power system first-wall applications.

• CATEGORY C – CAPABILITY TEAMS: Applicants seeking to contribute an expert or specialist capability that could assist multiple Category A and/or B experimental teams in fulfilling program objectives should consider selecting Category C.

Category C capability teams will support analysis and facilitate communications between Category A and B project teams and fusion power system designer end users by performing techno-economic analyses (TEA) and life-cycle analyses (LCA) of their materials products.

CHADWICK continues ARPA-E’s history of enabling innovative fusion technologies. The program joins the Agency’s fusion portfolio, which includes the ALPHA (earlier post); BETHE (earlier post); and GAMOW (earlier post) programs.

ALPHA supported the development of low-cost plasma heating and confinement concepts for future fusion energy systems. BETHE projects are improving the performance of inherently lower-cost fusion concepts, improving the economics of higher-performance concepts, and supporting capability teams to apply existing capabilities (e.g., theory/modeling, machine learning, or diagnostic) to accelerate the development of multiple concepts. GAMOW supports a wide range of fusion technologies outside of the fusion plasma to enable commercially attractive fusion energy.