Structural and magnetic stability of an amorphous Fe-based alloy with a wide supercooled liquid region

Autor: P. Vojtanik, H. Sassik, R. Andrejco, Rastislav Varga, R. Grössinger
Rok vydání: 2004
Předmět:
Zdroj: physica status solidi (a). 201:1463-1470
ISSN: 1521-396X
0031-8965
Popis: The magnetic after-effect of initial reluctivity in an amorphous Fe73Al5Ga2P10C5B4Si1 alloy has been investigated by isochronal as well as isothermal measurements. The relaxation intensity is lower than in simpler Fe-based amorphous alloys prepared by rapid quenching methods. This is produced by reduced free volume quenched within the sample during manufacturing and by strong chemical bonds between metalloid atoms and atoms improving the glass-forming ability of the alloy. Changes of pre-exponential factor indicate large changes of amorphous structure after different heat treatments. Different relaxation mechanisms are identified in the samples, reorientation of atom pair axes and short-range metalloid migrations leading to homogenization of the structure and reduction of the free volumes. The most probable activation energy Q* and pre-exponential factor τ0 are lowest for as-prepared samples: Q* = 1.42 eV and τ0 = 3 × 10−16 s. Both these quantities increase after annealing and slow cooling to Q* = 1.79 eV and τ0 = 2 × 10−15 s. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Databáze: OpenAIRE
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