Bioinspired design and toughening mechanism of the TC4-(γ-TiAl/α2-Ti3Al) laminated composite fabricated by spark plasma sintering

Abstract Inspired by nature, new bioinspired TC4-(γ-TiAl/α2-Ti3Al) laminated composite with nacre-mimetic lamellar and brick-and-mortar architectures was fabricated by spark plasma sintering for the first time. The results indicated that the composite displayed a unique micro-laminated structure, composing of alternating γ-TiAl/α2-Ti3Al duplex phase alloy layer and TC4 titanium alloy layer. The composite showed a significant increase in fracture toughness while maintaining appropriate flexural strength at room temperature. Bioinspired design played an important role in toughening by complicated crack propagation, interconnecting structure, and synergistic effects of layers.