The Specific Heat of COPPER(3)GOLD.
Abstract
The specific heat of a Cu(,3)Au long ribbon shaped filament was measured with an A.C. heating method. The filament formed one of the elements of a Kelvin bridge which balanced out the voltage at the fundamental driving frequency. The resistance fluctuated with the temperature during the heating cycle. This generated a voltage at the third harmonic frequency which was related to the specific heat. The experimental problem was to separate the third harmonic signal, which was only 10-100 (mu)V from the noise and the harmonic distortion of the current source. Much of the electronic equipment used to do this was wired on an E.A.I. TR48 analog computer. The purpose of measuring the specific heat was to study the kinetics of the order-disorder process. The curve of equilibrium specific heat versus temperature shows a cusp near the transition temperature. The high values of specific heat below the transition temperature indicate that energy is needed to reduce the order as well as to increase the temperature. The values of specific heat we measured corresponded with the weighted average of the specific heat of pure Cu and pure Au. This indicates that there is no appreciable change in the short range order during one cycle.
- Publication:
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Ph.D. Thesis
- Pub Date:
- 1977
- Bibcode:
- 1977PhDT.......119P
- Keywords:
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- Physics: Condensed Matter