Tungsten-copper laminated composites are promising materials for high heat-flux applications, but their performance is often limited by interfacial instability caused by the thermal-mechanical mismatch between tungsten and copper. In this study, W/W-30Cu/CuCrZr three-layer composites are fabricated by high-pressure torsion (HPT) processing. Experimental characterization and molecular dynamics (MD) simulations are used to systematically investigate the influence of HPT process parameters and intermediate-layer composition on the evolution of microstructure and mechanical properties. HPT processing significantly refines the grains of the W-xCu composites and enhances their homogeneity. After applying 15 revolutions of HPT on W-30Cu composites, the crystallite size decreases by about 45.3%. The dislocation density increases to 5.95 × 10¹⁴ m⁻². The interfacial transition zone of tungsten-copper three-layer composites is continuous and stable after HPT processing, and the microhardness is gradient increasing along the radial direction, showing good stress coordination ability and interfacial bonding characteristics. With the increase of W content, the yield strength of W-xCu alloy increases significantly, but the ductility decreases. The W-30Cu system achieves the optimal balance between strength and ductility. At the same time, in the W/W-Cu/Cu model, as the number of dislocations increases, the yield stress and elastic modulus increase by about 15% and 22%, respectively, indicating that the high-density defects introduced by HPT have a significant strengthening effect on the composite system. This study provides an important theoretical basis and experimental support for the microstructure control and performance optimization of tungsten-copper laminated composite material.

The heterostructure preparation in Mg-rare earth (RE) alloy has attracted much attention due to the excellent enhancement of strength and ductility. However, the effect of heterostructure composition on mechanical properties in Mg-RE alloy is still not clear. In this work, three types of heterostructures with different composition induced by lamellar 14H long period stacking ordered (LPSO) phase were achieved in the Mg-Gd-Y-Zn-Zr alloys after cyclic extrusion and compression (CEC). The heterostructure was mainly composed of dynamic recrystallization (DRX) grains, deformed coarse grains, multiscale LPSO phase (blocky, granular, lamellar LPSO phase). The strength and ductility of Mg-Gd-Y-Zn-Zr alloy with heterostructure were simultaneously improved. The DRX behavior during CEC process was largely affected by the lamellar LPSO phase. The lamellar LPSO with large spacing (~92 nm) and low thickness (~13.46 nm) is easy to occur kinking behavior and the zigzag kinking area can serve as nucleation sites to promote DRX behavior. While the lamellar LPSO phase with high thickness (~23.41 nm) and similar spacing (~82 nm) was ruptured into granular LPSO phase and thus increase the volume fraction of granular LPSO phase, which made a great contribution to DRX behavior by particle stimulated nucleation. The main deformation mechanism of solution treatment + furnace cooling (SF) sample during CEC process is dominated by the multiple slips composed of basal slips, prismatic slips and pyramidal slips. For the solution treatment + air cooling (SA) sample and solution treatment + ageing treatment (ST) sample, the activation of basal slips is the critical deformation mechanism. The main contribution to yield strength is from the grain boundary, dislocation and hetero-deformation induced (HDI) strengthening. Moreover, the HDI strengthening in the SF and SA sample after CEC deformation is much larger than that of ST sample due to the distinct heterostructure composition.