Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Activity of hydrogen in metal-hydrogen systems: strontium, thorium-nitrogen, and vanadium alloys

Technical Report ·
OSTI ID:6864540

The dissolution of H gas has been studied using pressure-composition isotherms in Sr, Th-N and V alloys containing either Nb, Cr or Ti. Direct H equilibrium vapor pressure measurements were performed in the Sr-H and Th-N-H systems at 973 to 1173/sup 0/K and 623 to 1123/sup 0/K, respectively. Isopiestic solubility was used to measure the H equilibrium pressures for the V alloys at 223 to 473/sup 0/K. In all the alloys studied, the reaction of hydrogen with the metal phase was exothermic and hydrogen followed Sieverts' law over a considerable range of hydrogen concentration. The enthalpy of solution of H in the Sr and the enthalpy of formation of ThNH/sub x/ are -14.3 +- 1.2 kcal;/mol H and -16.3 +- 1.5 kcal/mol H/sub 2/, respectively. Enthalpies of solution of H for the V alloys ranged from -8.0 to -10.5 +- 0.3 kcal/mol H. Additions of T to V dramatically enhanced the isopiestic solubility of H, Cr significantly reduced the solubility and Nb moderately increased the solubility. Sieverts' law behavior for H in the V alloys showed that substitutional atoms did not act as deep traps for H.

Research Organization:
Ames Lab., IA (USA)
DOE Contract Number:
W-7405-ENG-82
OSTI ID:
6864540
Report Number(s):
IS-T-998; ON: DE83004976
Country of Publication:
United States
Language:
English