Improving the glass-forming ability and plasticity of a TiCu-based bulk metallic glass composite by minor additions of Si

Author(s)

Gargarella, P. ^{[1, 2]} ; Pauly, S. ^[2] ; Khoshkhoo, M. Samadi ^{[2, 3]} ; Kiminami, C. S. ^[1] ; Kuehn, U. ^[2] ; Eckert, J. ^{[4, 5]}

Affiliation

^[1] Univ Fed Sao Carlos, Dept Engn Mat, Rodovia Washington Luiz, Km 235, BR-13565905 Sao Paulo - Brazil

^[2] IFW Dresden, Inst Komplexe Mat, Helmholtzstr 20, D-01069 Dresden - Germany

^[3] Carl Zeiss Microscopy GmbH, Carl Zeiss Promenade 10, D-07745 Jena - Germany

^[4] Austrian Acad Sci, Erich Schmid Inst Mat Sci, Jahnstr 12, A-8700 Leoben - Austria

^[5] Univ Leoben, Dept Mat Phys, Jahnstr 12, A-8700 Leoben - Austria

• Document type: Journal article
• Source: Journal of Alloys and Compounds; v. 663, p. 531-539, APR 5 2016.
• Web of Science Citations: 12

Abstract

In this work, the effect of Si additions on the glass-forming ability (GFA) and the mechanical behaviour of a Ti42.5Cu42.5Ni7.5Zr7.5 alloy is investigated. An optimum GFA occurs for addition of 0.5 at% Si and it is explained based on a balance between two factors: an increased thermal stability of the supercooled liquid and the detrimental effect of Ti5Si3 on vitrification. On rapid cooling, composites consisting mainly of the cubic B2 phase and glass can form. Their plasticity increases with increasing Si additions without sacrificing their high yield strength. A characteristic core-shell microstructure is formed in the rod with 2 at% Si, for which the combination of an amorphous outer surface and a refined dendritic structure in the centre gives rise to a composite with enhanced mechanical properties. (C) 2015 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 13/05987-8 - Processing and characterization of amorphous, metastable and nano-structured metallic alloys
• Grantee: Claudio Shyinti Kiminami
• Support Opportunities: Research Projects - Thematic Grants