High-Speed (Subsecond) Measurement of Heat Capacity, Electrical Resistivity, and Thermal Radiation Properties of Tantalum in the Range 1900 to 3200 K.

Measurements of heat capacity, electrical resistivity, hemispherical total and normal spectral emittances of tantalum above 1900 K by a pulse heating technique are described. Duration of an individual experiment, in which the specimen is heated from room temperature to near its melting point, is less than one second. Temperature measurements are made with a photoelectric pyrometer. Experimental quantities are recorded with a digital data acquisition system. Time resolution of the entire system is 0.4 ms. Results on the above properties of tantalum in the range 1900 to 3200 K are reported and are compared with those in the literature. Estimated inaccuracy of measured properties in the above temperature range is 2 to 3 percent for heat capacity, 0.5 percent for electrical resistivity, 3 percent for hemispherical total emittance, and 2 percent for normal spectral emittance.