Accession Number : AD0785014

Title :   Superconducting Properties of Bulk and Thin Film Al5 Compounds,

Corporate Author : MINNESOTA UNIV MINNEAPOLIS DEPT OF CHEMICAL ENGINEERING AND MATERIALS SCIENCE

Personal Author(s) : Somasundaram,Ramasubramanian ; Toth,Louis E. ; Spitzer,Hermann

Report Date : 1973

Pagination or Media Count : 118

Abstract : Superconducting properties of cast and heat treated alloys of niobium with Al, Ge and Ga were studied as a function of composition and heat treatment. Structure and composition of alloys were studied with X-rays, metallography and electron-microprobe analysis. These studies indicated that the improvement in transition temperature resulted from changes in composition of the Al5 phase which occur during heat treatment. Thin films of some of the Al5 Nb alloys were sputtered as a function of applied voltage and substrate temperature from a compound target. Sputtered films of Nb-Sn with a Tc of 15.6 K and Nb-Ge films with a Tc of 17 K were obtained. Sputtered films of Nb-Al, Nb-Ga and Nb-Al-Ge had poor superconducting properties mainly due to the absence of the Al5 phase. The results indicated that the sputtering variables affect the superconducting properties by varying the structure and composition of the film. (Modified author abstract)

Descriptors :   *SUPERCONDUCTIVITY, NIOBIUM ALLOYS, ALUMINUM ALLOYS, GERMANIUM ALLOYS, GALLIUM ALLOYS, TRANSITION TEMPERATURE, THIN FILMS, BULK MATERIALS, HEAT TREATMENT, SPUTTERING, INTERMETALLIC COMPOUNDS, PHASE TRANSFORMATIONS, TIN ALLOYS, CRYSTAL STRUCTURE, THESES

Subject Categories : Properties of Metals and Alloys
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE