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This work describes a high-throughput experimental method to characterize compositional trends in the glass forming ability and mechanical behavior of a ternary metallic alloy system. Continuously-graded composition libraries of Cu-Zr-Ti ternary alloys were produced by laser deposition, and continuous regions of glass-forming compositions were rapidly identified through an optical microscopy technique. By varying the laser processing parameters and thereby the cooling rate of the melt within each library, the composition with the greatest glass-forming ability within the range studied was determined to be Cu 51.7 Zr 36.7 Ti 11.6. An alternative deposition scheme was applied to fabricate libraries containing a large array of discrete compositions. Instrumented nanoindentation was performed on the discrete libraries to establish compositional trends in the measured properties. The indentation modulus was observed to be strongly correlated with the Ti-content over the entire region of study, while the hardness was more sensitive to Cu for high Zr-contents and to Ti at lower Zrcontents. These trends could inform the design of new metallic glass alloys possessing an optimized balance of both ductility and glass forming ability.

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Compositionally graded Cu-Zr specimens covering a wide composition range (30 to 60 at. pct Zr) were fabricated by direct laser deposition. By observing the surface topography of the as-fabricated specimens with differential interference contrast microscopy, primarily amorphous regions corresponding to compositions of high glass-forming ability were rapidly identified. Electron diffraction results confirmed the relationship between surface topography and atomic structure. The compositional widths of the amorphous regions were observed to narrow with increasing heat input from the laser, enabling further identification of local maxima in the glassforming landscape of Cu-Zr alloys. In this work, we report two peaks in the glass-forming ability, located at Cu 64.7 Zr 35.3 and Cu 50.2 Zr 49.8 . These two compositions find excellent agreement with previously reported results based on casting of discrete compositions.

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