Nanoporous gold (NPG) possesses excellent physical and chemical properties, exhibiting widespread application potential. To enhance its mechanical performance, this study proposes a novel NPG architecture featuring preferentially aligned pore channels (pa-NPG) and systematically compares its mechanical behavior with that of conventional homogeneous NPG (h-NPG). Using phase-field modeling and molecular dynamics simulations, we generate both structures with various solid volume fractions. Uniaxial compression tests reveal that pa-NPG achieves a comprehensive enhancement in mechanical properties. Its elastic modulus is 30%–55% higher, and its energy absorption per unit volume exceeds that of h-NPG by 6.9%–16.5%. Scaling-law analysis of elastic modulus indicates that while h-NPG follows a classical bending-dominated behavior (exponent ∼2), pa-NPG manifests a hybrid mechanism dominated by combined ligament axial compression and bending. A modified Gibson–Ashby scaling law is proposed to describe the elastic behavior of pa-NPG. During the plateau regime, pa-NPG exhibits a higher density of HCP atoms, indicating stronger stacking fault/dislocation activity, which contributes to its sustained hardening and higher plateau stress. Furthermore, the deformation of individual ligaments confirms the significantly greater contribution of ligament axial compression in pa-NPG compared to the predominantly bending-dominated response in h-NPG, providing direct microstructural evidence for its enhanced load-bearing efficiency. These microstructural responses lead to a higher plateau stress and superior specific energy absorption in pa-NPG. This work provides a promising design strategy for lightweight structural materials with tailored mechanical performance.
Zhang et al. (Mon,) studied this question.