THE THERMODYNAMIC PROPERTIES OF THE SYSTEMS NB-H, V-H AND TA-H
Abstract
The equilibrium pressure method was employed to determine the solubility of H in Group VB metals in the temperature range 250 to 650 C, and for H pressures extending up to one atmosphere. Only a single solid solution phase was found throughout the experimentally investigated regions. In all three systems, however, the shape of the low-temperature isotherms clearly indicated the existence of two-phase immiscibility intervals. For all conditions, H was more soluble in Nb than it is in Ta or V. The solubility in Ta is higher than in V except for higher compositions, where the reverse is true. The maximum H solubility limits are independent of temperature and correspond to the atomic ratio 0.89 for Nb and V and 0.71 for Ta. Partial phase diagams constructed for the three systems include the proposed boundaries of the heterogeneous two-phase region. The thermodynamic properties determined from the experimental data were in good agreement with those calclated from the statistical model.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1960
- Accession Number
- AD0282433
Entities
People
- Ewald Veleckis
Organizations
- Illinois Institute of Technology