MEASUREMENTS OF THERMOPHYSICAL PROPERTIES OF NICKEL WITH A NEW HIGHLYSENSITIVE PYROMETER

A new, sensitive, and fast (response time, 100 ns) pyrometer used for the measurement of temperature in pulse heating experiments is describ ed. The monochromatic instrument may use two detectors, namely, a Si d iode and an InGaAs diode. Since monochromatic pyrometers usually are ' 'self-calibrated'' with the plateau of the melting transition of the i nvestigated metal, a high sensitivity is desirable. The pyrometer is s ensitive down to 1000 K and may be used at the melting plateau of copp er, a reference point on the international Temperature Scale of 1990. A wide temperature range in a single measurement is possible with the use of a fast operational amplifier with linear and logarithmic output s. Electrical resistivity, heat capacity, and enthalpy of nickel were measured in the temperature range 1500 to 2200 K using a fast pulse he ating technique.