PHYSICAL PROPERTIES OF HIGH TEMPERATURE MATERIALS. PART II. THE HEAT CAPACITY OF ZIRCONIUM, SEVERAL ZIRCONIUM HYDRIDES, AND CERTAIN CLADDING MATERIALS FROM 0 TO 900 C RELATION TO OTHER THERMODYNAMIC PROPERTIES OF THE Zr-H SYSTEM. Perioc covered June 1955 to September 1955 and June 1956 to July 1957

Technical Report · Thu Aug 01 04:00:00 EDT 1957

OSTI ID:4345670

Douglas, T B; Victor, A C

Using accurate apparatus and a drop'' method, the heat content (enthalpy) of Zr, five Zr hydrides (NH from 1.34 to 4.14), and stainless steel type 316 were measured over the range from 0 to 900 deg C. Using the values for the stainless steel and those from the literature for Mo and Nb, the heat capacities of typical clad samples of the hydrides may be computed additively. Thermal hysteresis of the hydrides was investigated in several cases. Corrections were applied for the impurities in the samples measured, but the two sets of hydrides gave heat values believed to be somewhat inconsistent in the range 550 to 800 deg C through systematic differences in phase compositions. The heat content data were extensively correlated with certain published equilibrium data for the Zr-H in order to extend knowledge of the heats of hydriding, equilibrium H/sub 2/ pressures, and limits of solid solubility to wider ranges of temperature and composition than those covered by direct measurements. The results are discussed critically, and several structural implications are pointed out. (auth)

• Research Organization: National Bureau of Standards, Washington, D.C.
• NSA Number: NSA-12-002351
• OSTI ID: 4345670
• Report Number(s): WADC-TR-57-374(Pt.II)
• Country of Publication: United States
• Language: English

Related Subjects

COATING
HIGH TEMPERATURE
HYSTERESIS
IMPURITIES
LABORATORY EQUIPMENT
MEASURED VALUES
MINERALOGY, METALLURGY, AND CERAMICS
MOLYBDENUM
NIOBIUM
PHASE DIAGRAMS
PRESSURE
QUANTITY RATIO
REACTION KINETICS
SAMPLING
SOLIDS
SOLUBILITY
SPECIFIC HEAT
STAINLESS STEELS
TEMPERATURE
THERMODYNAMICS
ZIRCONIUM HYDRIDES