Material Performance in Helium-Cooled Systems

Abstract

Very high-temperature helium gas-cooled reactors are being developed for processing heat applications and hydrogen generation. Nickel-based solid-solution alloys will very likely be used in these reactors for heat exchangers, core barrel, and control rod sleeves. Mechanical properties and resistance to aging and environmental degradation in helium primary coolant at temperatures above 800°C that are critical to successful application of this technology are reviewed in this article. Further research and development needs for advanced joining and nondestructive examination methods and ceramic composite materials for very high-temperature application are identified.