Tuning interfacial mechanical properties of Ti/CFRP laminates using customized intercalation of woven metallic fabrics

Abstract

Improving the interlaminar fracture toughness of fiber metal laminates comprising titanium alloy (Ti) and carbon fiber-reinforced polymer (CFRP) holds considerable significance for their diverse applications. Here, an innovative and scalable strategy was developed to enhance the interfacial adhesion of Ti/CFRP hybrid laminates, which was achieved by introducing customized woven metallic fabrics to construct a heterogeneous interface through a simple and cost-effective spot welding method. Interestingly, it was found that the interlaminar mechanical performance and failure mode transition from snap-down instability to progressive softening behavior could be precisely tuned by adjusting the distribution configurations of the welded spots. The results demonstrated substantial improvements in interlaminar fracture energies with the implementation of customized intercalation. Specifically, mode I initiation and propagation were enhanced by approximately 276% and 144%, respectively, while mode II initiation improved by approximately 242%. These improvements were attributed to the activation of new dissipative mechanisms, including interfacial topological texture interlocking, adhesive failure, multiphase bridging (involving woven metallic fabric, welded spots and carbon fiber), as well as cross-layer migration of the interlaminar cracks. The use of customized intercalation thus proves to be a promising strategy for constructing heterogeneous interface and offers valuable insights into the interlaminar design for hybrid structures.