Combinatorial development of bulk metallic glasses

Abstract

The identification of multicomponent alloys out of a vast compositional space is a daunting task, especially for bulk metallic glasses composed of three or more elements. Despite an increasing theoretical understanding of glass formation, bulk metallic glasses are predominantly developed through a sequential and time-consuming trial-and-error approach. Even for binary systems, accurate quantum mechanical approaches are still many orders of magnitude away from being able to simulate the relatively slow kinetics of glass formation. Here, we present a high-throughput strategy where ∼3,000 alloy compositions are fabricated simultaneously and characterized for thermoplastic formability through parallel blow forming. Using this approach, we identified the composition with the highest thermoplastic formability in the glass-forming system Mg-Cu-Y. The method provides a versatile toolbox for unveiling complex correlations of material properties and glass formation, and should facilitate a drastic increase in the discovery rate of metallic glasses.

Structure in sheared supercooled liquids: Dynamical rearrangements of an effective system of icosahedra

“…In particular, a drop in the population of icosahedra in the shear bands seems entirely consistent with the idea that icosahedra are involved in the increased rigidity of the Wahnström model. This is also consistent with the negative correlation identified between locally weak "soft spots" and icosahedra in a metallic glassformer [68] and banding behaviour [69,70]. Fitting the shear bands with our population dynamics model [25] suggests that the banding regions can be treated as if they are at a higher effective temperature.…”

High-Throughput Exploration of Evolutionary Structural Materials

“…Dies ermöglicht computergestütz-tes Materialdesign mit DFT-Modellen [7][8][9]. Heute sind Dünn-schicht-Hochdurchsatz-Techniken ein verbreitetes Versuchswerkzeug für die Entwicklung von Funktionswerkstoffen [10][11][12]. Gradierte Dünnschicht-Techniken können ganze ternäre oder quaternäre Legierungssysteme auf einem einzelnen Träger evaluieren.…”

“…Today, thin film high throughput techniques are a common experimental tool for the development of functional materials [10][11][12]. Graded thin film techniques can evaluate whole ternary or quaternary alloy systems on a single substrate.…”

Criticality in Bulk Metallic Glass Constituent Elements

“…26 The selection criteria for BMGforming elements include their relative size, 2,4,27,28 their thermodynamic attraction quantified in the pairwise heat of mixing, 2,29,30 and the stability of the liquid compared with the crystal. [31][32][33] The latter is quantified by the suppression of the liquidus temperature compared with the weighted rule of mixing of the melting temperature of the constituents.…”