Thermodynamics of Chemical Species Important to Rocket Technology.
Abstract
Using a subsecond-duration transient technique, the specific heat, electrical resistivity, and hemispherical total emittance were simultaneously measured over the temperature range 1500-2800K for iron and for the alloy 80 Nb-10 Ta-10 W. The work on iron demonstrates the feasibility of applying a rapid-pulse heating technique to solid-solid transformations. Melting points (and normal spectral emittance for 650 nm at the melting point) were found. Preliminary values are reported for the first time for the standard heat of formation and a vapor pressure of the subfluoride of molybdenum MoF5. A new static method for measuring small vapor pressures has reproduced known values for I2 and MoF6 to within 1%. The vapor pressure of MoF5 (l) thus measured at 393K, when compared with the earlier transpiration result for this temperature, indicates that the saturated vapor contains about 85 or 90 mole % of the monomer species, depending on the method of interpretation. (Modified author abstract)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1973
- Accession Number
- AD0782028
Entities
People
- Charles W. Beckett
- Thomas B. Douglas
Organizations
- National Institute of Standards and Technology