Effects of microalloying with 3d transition metals on glass formation in A1YFe alloys

TitleEffects of microalloying with 3d transition metals on glass formation in A1YFe alloys
Publication TypeJournal Article
Year of Publication2007
AuthorsBondi KS, Gangopadhyay AK, Marine Z, Kim TH, Mukhopadhyay A, Goldman AI, Buhro WE, Kelton KF
Journal TitleJournal of Non-Crystalline Solids
Volume353
Pages4723-4731
Date PublishedDec
Type of ArticleArticle
ISBN Number0022-3093
Accession NumberISI:000252513800015
Keywordsalloys, amorphous metals, CRYSTALLIZATION, diffusion and transport, glass formation, glass transition, glasses, me, metallic glasses, nano-composites, nucleation, rare-earth in glasses, STEM/TEM, Synchrotron radiation, transition metals, x-ray diffraction
Abstract

The effects of microalloying on glass formation and stability were systematically investigated by substituting 0.5 at.% of all 3d transition metals for Al in Al88Y7Fe5 alloys. X-ray diffraction and isothermal differential scanning calorimetry studies indicate that samples containing microadditions of Ti, V, Cr, Mn, Fe and Co were amorphous, while those alloyed with Ni and Cu were not. The onset temperatures for crystallization (devitrification) of the amorphous alloys were increased with microalloying and some showed a supercooled liquid region (Delta T-x = T-x - T-g) of up to 40 degrees C. In addition, microalloying changes the glass structure and the devitrification sequence, as determined by differential scanning calorimetry (DSC), X-ray diffraction (XRD), transmission electron microscopy (TEM), differential thermal analysis (DTA) and high energy X-ray diffraction. The results presented here suggest that the order induced in the alloy by the transition metal microaddition decreases the atomic mobility in the glass and raises the barrier for the nucleation of alpha-Al, the primary devitrifying phase in most cases. New intermetallic phases also appear with microalloying and vary for different transition metal additions. (c) 2007 Elsevier B.V. All rights reserved.

DOI10.1016/j.jnoncrysol.2007.06.063
Alternate JournalJ. Non-Cryst. Solids