Laser additive manufacturing of laminated bulk metallic glass composite with desired strength-ductility combination

Abstract

Introducing ductile crystalline dendrites into a glassy matrix to produce bulk metallic glass composites (BMGCs) is an effective way to improve the poor ductility of bulk metallic glasses (BMGs). However, the presence of soft crystalline phases tends to decrease the strength and causes the strength-ductility tradeoff. Here, relying on the flexible laser additive manufacturing (LAM) technique that allows the composition tailoring of each layer, we successfully fabricate a lamellated Zr-based BMGC constructed by the alternating superimposition of soft and hard layers. The lamellated BMGC shows an exceptional combination of yield strength (∼1.2 GPa) and ductility (∼5%). Such enhanced strength-ductility synergy is attributed to the asynchronous deformation at two scales, i.e., inter-laminar and intra-laminar, and the unique dual-scale Ta particles that uniformly distribute on the amorphous matrix. The lamellated structure design motif, enabled by the flexible LAM technology, provides a new window for the development of high-performance BMGCs. It is also applicable to the synergistic enhancement of strength and plasticity of other brittle metallic materials.