Crystalline layer on the surface of Zr-based bulk metallic glasses

Citation
Ge. Abrosimova et al., Crystalline layer on the surface of Zr-based bulk metallic glasses, J NON-CRYST, 288(1-3), 2001, pp. 121-126
Citations number
16
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
JOURNAL OF NON-CRYSTALLINE SOLIDS
ISSN journal
00223093 → ACNP
Volume
288
Issue
1-3
Year of publication
2001
Pages
121 - 126
Database
ISI
SICI code
0022-3093(200108)288:1-3<121:CLOTSO>2.0.ZU;2-R
Abstract
The structure, stability and microstructure Of Zr65Cu17.5Ni10Al7.5 and Zr50 Cu18Ni17Ti5Al10 bulk amorphous alloys was studied by X-ray diffraction, dif ferential scanning calorimetry, and scanning electron microscopy. A thin cr ystalline surface layer was observed on both bulk metallic glasses. This la yer consists of zirconium carbide and some crystalline phases. The thicknes s of the layer varies between 5 and 10 mum, it depends on the location in t he sample. The origin of the formation of the crystalline layer is discusse d. The formation of the crystalline layer is connected with carbon depositi on on the sample surface during the production of the metallic glass, and w ith select carbide formation. The resulting change of the concentration of the alloy components near the surface due to the carbide formation leads to a shift of the alloy composition from the amorphization region and results in further crystallization of near surface regions. (C) 2001 Elsevier Scie nce B.V. All rights reserved.