Plating Investigation for Aluminum Tritium Scroll Vacuum Pump to Improve Durability and Decrease Overall Cost

For handling radiated gases between the tritium T evacuation systems and the magnetic fusion chamber, scroll pumps have been the institutionally preferred solution because of their lack of any polymer seals, eliminating the possibility of contamination, allmetal stainlesssteel design, impermeable by the radioactive T, and double bellows containment that provided redundant safety precautions. However, fusion research and development is still limited by steep production costs, longlead times, and the difficulty of machining scroll vacuum pumps from stainlesssteel. Stainlesssteel is universally recognized as the only reliable means to contain radioactive T in fusion vacuum trains but little research has been conducted to evaluate the performance and permeability of alternative T handling materials that could significantly reduce capital cost, shorten development schedule, and simplify the adoption and commercialization of fusion reactor components. This SBIR proposes to conduct a T containment performance and permeability study to evaluate the effectiveness of safe T handling utilizing easily machined aluminum plated with nickel or other elements to replace stateoftheart stainlesssteel T containment. The project intends to show that alternative plated aluminum can maintain the same impermeability of stainlesssteel throughout the expected lifetime of T handling components while maintaining or improving performance. Five test aluminum test sample coupons were manufactured at Air Squared’s Colorado Headquarters and tested for added adhesion, hardness, surface finish, thickness, plating buildup, and flatness. Then, two scroll vacuum pumps were fabricated and plated to be tested for their vacuum performance in a magnetic fusion tritiated environment in Phase II. In Phase II, Air Squared will evaluate additional methods of reducing costs, manufacturing lead times, and weigh of plated aluminum scroll roughing vacuum pumps while also increasing the T pump’s performance. Air Squared is confident that evaluating the performance and permeability of stainlesssteel T containment alternatives will significantly reduce capital cost, shorten development schedules, and simplify commercialization of future nuclear fusion components. Verifying inexpensive, easily machined materials can safely handle radioactive working fluids will appreciably lower economic barriers to entry for and accelerate nuclear fusion research. Scroll vacuum pumps adapted with successfully evaluated materials after Phase II could be universally adopted and replace stainlesssteel pumps worldwide at over sixty nuclear fusion research institutions.