Abstract : Work prior to this reporting period focused on achieving a more inert atmosphere for handling and consolidation of the nano-scaled steel powders. As a result, oxygen content in the nano steel powder compacts has been decreased significantly. However, even the decreased level (3% to 5%) is still too high. Further, high carbon levels (6% to 10%) which originate from the chemical synthesis of the powder, were also observed in the powder compacts. Treatment of the nano-scaled powder in a hydrogen retort would reduce the carbon and oxygen contents. Therefore, a study the effects of hydrogen treatment temperature on the interstitial contents was conducted during this reporting period. Several batches of nano-scaled powders produced by sonication reactions were hydrogen treated using the selected temperature and then consolidated in the vacuum hot press.