Mechanical Properties of Metallic Glass Matrix Composites

Bulk metallic glass matrix composites (BMGMCs) are a new class of composite material, designed to take advantage of the impressive strength and high elastic limit of metallic glasses, while improving toughness and suppressing localized failure through the introduction of microstructure.  Depending upon the system thermodynamics and processing kinetics, the reinforcement phase in BMGMCs may itself be inherently ductile or brittle, and the second phase volume fraction is also often quite tailorable.  For example, the figure below shows an example of Zr-based glass composites with four different levels of reinforcing crystalline phase.  Our group studies the microstructure-property connections in BMGMCs, with special emphasis on mechanical properties.  At high temperatures, we investigate the flow rheology of composites for its implications in shape forming.  At low temperatures we study strength, plasticity, toughness, and interaction of shear bands with inclusion phases.  We also employ computer simulations to study the mechanics of this new class of composites.

See also the review article Mechanical Behavior of Amorphous Alloys in Acta Materialia

Scanning electron micrographs of (a) the Zr-based bulk metallic glass and the in situ composites used in this work, containing (b) 7%, (c) 15%, and (d) 20% of the dendritic second phase. These alloys have compositions Zr49Cu51-xAlx with x=6, 8, 10, and 12 at. %, for the four structures, respectively.

Published Articles:

Homogeneous flow of bulk metallic glass composites with a high volume fraction of reinforcement 
Fu XL, Li Y, Schuh CA; JOURNAL OF MATERIALS RESEARCH 22 (6): 1564-1573 JUN 2007 (PDF)

Temperature, strain rate and reinforcement volume fraction dependence of plastic deformation in metallic glass matrix composites 
Fu XL, Li Y, Schuh CA; ACTA MATERIALIA 55 (9): 3059-3071 MAY 2007 (PDF)

Mechanical properties of metallic glass matrix composites: Effects of reinforcement character and connectivity
Fu XL, Li Y, Schuh CA; SCRIPTA MATERIALIA 56 (7): 617-620 APR 2007 (PDF)

Critical length scales for the deformation of amorphous metals containing nanocrystals 
Lund AC, Schuh CA; PHILOSOPHICAL MAGAZINE LETTERS 87 (8): 603-611 AUG 2007 (PDF)

Contributions to the homogeneous plastic flow of in situ metallic glass matrix composites
Fu XL, Li Y, Schuh CA; APPLIED PHYSICS LETTERS 87 (24): Art. No. 241904 DEC 2005 (PDF)

Effect of a controlled volume fraction of dendritic phases on tensile and compressive ductility in La-based metallic glass
Lee ML, Li Y, Schuh CA; ACTA MATERIALIA 52 (14): 4121-4131 AUG 2004 (PDF)