ABSTRACT
I. INTRODUCTION In this chapter, the low-temperature properties of rapidly solidified alloys will be reviewed. As outlined in previous chapters, rapid solidification results in a variety of structures, for example, amorphous, microcrystalline, quasicrystalline. In this chapter, emphasis will be put on amorphous solids.* Many amorphous alloys exhibit superconductivity, and with the newly exploded interest in this field, it is only fair to begin with a brief elaboration of the superconducting properties of these materials, even if, nowadays, superconductivity is no longer restricted to very low temperatures. After a brief review of the basic features of BCS superconductors in Section IIA, Sections liB and C will treat superconductivity in amorphous simple metals and in amorphous alloys containing transition elements. Critical fields and electron-localization effects will be the subject of Section liD. We will also discuss superconductivity of quasi-and microcrystalline alloys (Section liE). In Section IIF we will briefly review the impact of rapid solidification techniques on high-T, superconductors. In the spirit of this book, we will restrict ourselves to rapid solidification from the melt. Vapor deposition, sputtering, and laser ablation techniques which are, of course, also rapid solidification processes, are widely used to prepare high-Tc films. However, even a rough overview would be beyond the scope of this chapter, in view of the numerous papers and rapid advance in this subject.
