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Antares achieves zero-power criticality at INL
Leveraging more than $140 million in private capital fundraising, over 322,000 square feet of operational manufacturing space, and multifaceted partnerships with the Departments of Energy and Defense, reactor start-up Antares has become the first company involved in the Reactor Pilot Program to achieve zero-power fueled criticality—a full month ahead of the July 4 deadline set by President Trump’s Executive Order 14301.
This milestone, announced yesterday, was achieved with the company’s Mark-0: a sodium heat-pipe-cooled, TRISO-fueled microreactor. The Mark-0 is a forerunner to the company’s flagship design, which it calls the R1. For Antares, this development represents a key validation of its reactor physics, control systems, and supply chain.
Kirk L. Shanahan
Fusion Science and Technology | Volume 71 | Number 4 | May 2017 | Pages 555-564
Technical Note | doi.org/10.1080/15361055.2017.1291042
Articles are hosted by Taylor and Francis Online.
Tritium decays to 3He, and when this decay occurs inside a metal tritide, the 3He is largely retained in the material’s bulk. This impacts the subsequent behavior of the hydrogen isotope absorption and desorption, altering the materials thermodynamic characteristics. Chemical substitution can form alternative miscible hydridable metal alloys over some concentration ranges with modified thermodynamic properties. This allows the ‘tuning’ of metal hydride characteristics to expand the inventory of available materials for use, potentially allowing a closer match to desired performance characteristics. It is important to quantify tritium aging effects in order to predict the long term, in-process behavior of metal hydride materials. The Savannah River National Laboratory has been interested in elucidating the impact of tritium exposure on the behavior of hydrideable metals and metal alloys. Pd alloy foils of nominal 5 and 9 at% Cr, Ni, and Co, were loaded with tritium, and stored for ~1 year in static storage. One sample (Pd-4.8 at% Ni) was subsequently stored for an additional ~3 years. Isotherms were determined following storage periods to study the tritium induced changes caused by tritium decay. Typical effects such as plateau pressure depression and heel formation were noted. The materials proved to be unusually sensitive to the isotherm determination process and decay effects were partially reversed, or “healed”. The Pd-4.8wt%Ni sample was removed from its storage unit, whereupon it was found to have turned into powder, and further studied with additional techniques elsewhere.