Wyniki wyszukiwania - BazTech

Ograniczanie wyników

2 1998

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

'oxide/oxide' superconductor materials: electrical properties of Bi-2212/insulator composites.

Tortet L., Monnereau O., Alfred-Duplan C., Vacquier G.

Inżynieria Materiałowa

1998

R. XIX, nr 4

872-875

To reinforce the electrical or mechanical properties of bismuth cuprate superconductor, composites have been elaborated by pressing polycrystalline Bi2Sr2CaCu2O8-6 (2212) mixed with two insulator oxides into pellets, which ares intered near 800 centigrade C. A large domain of composition is investigated. The Bi2CuO4 (2001) oxide reacts with the Bi-2212, decreases its Tc value but can increase its mechanical resistance. In the case of Bi2Sr3CaO7-6/2212 composites, a zero resisntance at low temperature (>> 40 K) is observed up to 80% (vol.) of insulting (2310) oxide. The percolation theory of the Effektive Medium Approximation are used to describe these experimantal results.

Evidences of the formation of a conductive Al film on AlN surface under UV excimer laser radiation.

Yaghdjian L., Nicolas G., Vacquier G., Autric M.

Inżynieria Materiałowa

1998

R. XIX, nr 4

1051-1056

Surface modifications of an AlN ceramic under an UV excimer laser irradiation have been investigated by SEM observations and EDS analysis, grazing-XRD and electrical resistance measurements. XRD have revealed the presence of an Al metallic film upon the laser impacted zone and SEM+EDS analysis have showed the formation of halo rich in oxygen around it. Electrical measurements have confirmed the metallic nature of the impacted surface, where a conductive path can be drawn upon the insulator AlN ceramic. Laser conditions have been determined regarding to the obtention of a metallic film by this one-step process.