Severe plastic deformation promoted simultaneous enhancement in strength and ductility of multilayer MXene/Ag matrix composites

The insufficient mechanical performance of Ag poses a critical challenge for its application as an electrical contact material. In this study, a strategy was developed that employed severe plastic deformation to design a strong and ductile 3 vol% MXene/Ag matrix composite. Multilayer MXene was randomly incorporated into an Ag matrix via a heteroagglomeration process and spark plasma sintering. After hot extrusion, the MXene became preferentially oriented along a single direction owing to the metallic plastic flow. Moreover, the high shear stress exerted by the Ag matrix facilitated the exfoliation of the accordion-like MXene, resulting in a reduced thickness. Consequently, the tensile strength and elongation of the hot-extruded MXene/Ag composite improved by 59 % and 676 %, respectively, primarily due to the prevention of delamination between adjacent accordion flakes and the enhanced strengthening contribution of MXene. This study demonstrated the fabrication of high-performance Ag-based composites by leveraging the exceptional properties of two-dimensional MXene and the intrinsic features of the consolidation process.