Superconductivity In Metals And Alloys
Report Number: WADD TR 60-919
Author(s): Cherry, W. H. , Gittleman, J. I. , Hanak, J. J., McConville, G. T., Rosi, F. D., Cody, G. D.
Corporate Author(s): RCA Laboratories
Laboratory: Directorate of Materials and Processes
Date of Publication: 1961-06
Pages: 53
Contract: AF 33(616)-6405
DoD Project: 7371
DoD Task: 73711
Identifier: AD0268781
Abstract:
Methods have been developed for the measurement of the interphase energy in superconductors. A description of the method is given along with preliminary results on thin foils and films of tin. A proposed examination of the thermal contact resistance (Kapitza resistance) between metals and liquid helium is described. The apparatus is designed to measure changes in this contact resistance at the superconducting transition as well as in the normal state. Measurements of the effect of hydrogen and deuterium on the superconducting transition temperature of lanthanum have revealed that they both depress the transition temperature.; hydrogen depresses the transition temperature more than deuterium. Measurements were made of the transition temperatures in the system (Nb, Ta, V)3Sn. The transition temperatures range from 2.8°K to 18°K and can be related to a simple mass and volume dependence. Critical field measurements indicate behavior similar to that in other "hard" superconductors. Resistance measurements revealed a resistance anomaly near 100°K which can be related to an existing theory. It has been found possible to prepare films of Nb3Sn by a transport reaction. Alloying experiments indicate ambiguities in the electron-to-atom ratio ascribed to various elements.
Provenance: IIT
Author(s): Cherry, W. H. , Gittleman, J. I. , Hanak, J. J., McConville, G. T., Rosi, F. D., Cody, G. D.
Corporate Author(s): RCA Laboratories
Laboratory: Directorate of Materials and Processes
Date of Publication: 1961-06
Pages: 53
Contract: AF 33(616)-6405
DoD Project: 7371
DoD Task: 73711
Identifier: AD0268781
Abstract:
Methods have been developed for the measurement of the interphase energy in superconductors. A description of the method is given along with preliminary results on thin foils and films of tin. A proposed examination of the thermal contact resistance (Kapitza resistance) between metals and liquid helium is described. The apparatus is designed to measure changes in this contact resistance at the superconducting transition as well as in the normal state. Measurements of the effect of hydrogen and deuterium on the superconducting transition temperature of lanthanum have revealed that they both depress the transition temperature.; hydrogen depresses the transition temperature more than deuterium. Measurements were made of the transition temperatures in the system (Nb, Ta, V)3Sn. The transition temperatures range from 2.8°K to 18°K and can be related to a simple mass and volume dependence. Critical field measurements indicate behavior similar to that in other "hard" superconductors. Resistance measurements revealed a resistance anomaly near 100°K which can be related to an existing theory. It has been found possible to prepare films of Nb3Sn by a transport reaction. Alloying experiments indicate ambiguities in the electron-to-atom ratio ascribed to various elements.
Provenance: IIT