Additive manufacturing of functional structure with enhanced mechanical and thermal properties enabled by micro-composition and macro-structural design

Effective thermal management requires functional structures with exceptional heat dissipation and load-bearing capabilities. Additive manufacturing (AM) enables their fabrication by achieving complex geometries inaccessible to traditional methods. This study introduces a parallel design methodology combining micro-compositional adjustments with macro-architectural optimization to engineer micro-lattices exhibiting superior thermomechanical performance. In terms of composition, 316-60 wt.% Cu composites exhibited the optimal balance of mechanical strength and thermal conductivity, achieving a tensile strength of 539 MPa and thermal conductivity of 81.5 W/(m·K), outperforming conventional heat transfer alloys. Leveraging the diamond lattice model, four micro-architectures with differing strut cross-sections were engineered and processed by Laser powder fusion (LPBF) to achieve integrated heat transfer and mechanical properties. Their printability, mechanical behavior, and thermal performance were systematically evaluated. A compressive yield strength range of 4.13–58 MPa was observed in micro-lattices. Synergistic application of finite element modeling and experimental analysis elucidated the critical role of strut geometric design on deformation mechanics and resultant mechanical performance, with multi-stage hierarchical layer failure identified as a dominant mechanism. Additionally, computational fluid dynamics simulations were employed to investigate the effects of strut shape on heat transfer performance. These findings offer valuable theoretical insights for advancing heat transfer applications in engineering.