Categorical Exclusion Determination
Office of NEPA Policy and Compliance
July 12, 2017
Estimated Read Time min
The Colorado School of Mines proposes to develop a fundamental understanding of microalloying precipitate design and thermomechanical treatment in high-alloyed steels to suppress void swelling and improve low temperature loss of ductility in HT-9 based alloys. The objective of this study is to use a science-based approach, combining thermodynamically- and experimentallyinformed alloy design and experimental performance evaluations (both before and after irradiation), to design and evaluate microstructures that (1) substantially reduce low temperature (300-400 degrees C) embrittlement by removing free nitrogen and (2) simultaneously create fine, stable precipitate dispersions by microalloying additions to improve strength, ductility, and irradiation resistance.