An Additively Manufactured Bionic Forest-like 3D Al₂O₃/Epoxy Architecture with Extraordinarily High Thermal Conductivity

With the critical requirements for the heat dissipation of 5G electronics, highly thermally conductive ceramic/polymer composites are commonly utilized due to their high thermal conductivity, good electrical insulation, and superior processability properties. The shift from conventional two-dimensional (2D) planar structures to three-dimensional (3D) structures is currently the primary focus of enhancing the thermal characteristics. In this study, enlightened by the forest cooling principle of the urban edge, bionic forest-like 3D Al2O3 structures (3D-A) were designed by topological optimization algorithms as a theoretical basis and prepared by vat photopolymerization (VPP) additive manufacturing. After sintering and compositing with epoxy, a bionic forest-like 3D Al2O3/epoxy (3D-AE) composite architecture was obtained successfully. The 3D-AE architecture achieved an extraordinarily high thermal conductivity of 15.76 Wm1–K–1 when the ceramic filler was 40 vol %, representing a remarkable 7778.2% improvement compared to neat epoxy. Besides, a high-power light-emitting diode (LED) with the 3D-AE architecture as a cooling substrate was set together concurrently to investigate the heat dissipation capability. Finite element analysis and infrared thermal imaging further validated the superior heat dissipation capabilities of 3D-AE. From this study, a quick and efficient technique for designing and creating 3D ceramic/polymer composite structures with high thermal conductivity was put forth by integrating topology optimization theory with biomimetic concepts and additive manufacturing.