Advanced wick structures for heat pipes and vapor chambers: a review on materials, design, and applications

High-heat-flux dissipation technology has become a key bottleneck restricting development in fields such as electronic information, new energy vehicles, aerospace, high-power semiconductor devices, and data centers. The heat transfer performance of heat pipes and vapor chambers mainly depends on the structural characteristics of their core part—the wick. Therefore, in-depth research on wick structures is of great practical significance for addressing the thermal management challenges in the fields. Focusing on metal-based wicks, this study combines a literature review with quantitative analysis and systematically classifies them into 4 major categories (with 13 subcategories). These four categories are homogeneous porous structures, biporous structures, composite structures, and other structures. The key influencing factors (such as particle size, pore size, thickness, and preparation process) and best parameter ranges of various wicks are systematically discussed, their heat transfer performance and application adaptability are compared, and a “scenario-parameter-performance” matching framework is set up. The results show that biporous metal powder wicks exhibit the best performance with respect to critical heat flux and superheat temperature; composite wicks possess both high capillary force and high permeability; homogeneous porous wicks are simple to prepare but have relatively limited performance. Notably, discrepancies between actual test results and theoretical predictions are mainly attributable to inconsistencies in test components (single-wick, assembled heat pipe or vapor chamber), dimensions, heating power, and cooling conditions. Based on the above findings, it can be inferred that the core of wick performance optimization lies in achieving a synergistic balance between capillary force and permeability, and in customizing parameters for specific application scenarios. This study proposes a refined classification system and conducts cross-type comparisons of their heat transfer performance, thereby providing a reliable reference for engineering applications. Future research should incorporate actual operating conditions, improve wick performance, perfect long-term reliability, standardize test methods, and promote the transformation of composite wicks from laboratory research to large-scale engineering applications.