Periodic electrodeposition of bio-inspired cauliflower-like structure wicks for vapor chambers

Wicks serve as essential elements in vapor chambers, with their capillary performance directly impacting the heat transfer capability. This study fabricated a electrodeposited wick with a cauliflower-like morphology at room temperature using a new periodic electrodeposition method. The influences of key parameters—such as current switching frequencies, number of cycles, current magnitudes, and electrode configuration methods—on the wick's morphology, capillary performance, and mechanical properties were experimentally examined. The wick porosity ranged from 52.7% to 84.4%, with the maximum capillary performance factor reaching 1.192 × 10⁻⁶ m. Compared to previous electrodeposited wicks, which typically exhibit fragile dendritic structures and require high-temperature heat treatment to enhance mechanical properties, the cauliflower-structured wick developed in this work combines robust mechanical strength with excellent capillary performance without the need for heat treatment, significantly improving the flexibility of the wick fabrication process. A vapor chamber produced with this advanced electrodeposition method exhibited excellent thermal performance, achieving a minimum thermal resistance of 0.136 °C/W at 320 W heating power with a 2 mL filling volume.