MXene-assisted interface engineering for strengthening aluminium matrix composites via high-pressure torsion

Owing to its intrinsic two-dimensional structure, combined with its functionalized surfaces and superior mechanical properties, Ti 3 C 2 T x (MXene) has emerged as a highly attractive candidate for reinforcing aluminium matrix composites (AMCs) in advanced structural applications. In this study, few-layer MXene (FMXene) was successfully incorporated into pure aluminium via an electrostatic self-assembly strategy followed by high-pressure torsion (HPT) processing at room temperature. The microstructure evolution of FMXene-Al composites was systematically investigated, revealing that this integrated processing strategy effectively induced grain refinement and facilitated the homogeneous dispersion of FMXene. The microhardness of the FMXene-Al composites increased with both the number of HPT turns and the FMXene content (wt.%), reaching a maximum value of approximately 140 HV. Notably, a favourable trade-off between strength and ductility was achieved at an FMXene content of 0.5 wt.%, where the ultimate tensile strength (UTS) reached 290 MPa while retaining appreciable ductility of ~ 1%. This work provides valuable insights into the development of nanostructured, high-performance AMCs via room temperature, interface-engineered processing routes. ▪ Room temperature self-assembly and HPT enabled uniform FMXene dispersion in aluminium (Al) matrix. ▪ No brittle Al 4 C 3 phase formed in HPT-processed FMXene-Al composites. ▪ Significant grain refinement (~400 nm) and enhanced mechanical properties with UTS 291 MPa and ~1% ductility in HPT-processed 0.5 wt.% FMXene-Al composite. ▪ Synergistic strengthening from grain refinement, load transfer, and interface pining.