【摘要】 消费电子器件的结构设计持续朝着小型化、轻量化方向迭代升级，对系统热管理技术提出了越来越严苛的要求。传统铜基和不锈钢基均热板在超薄化场景中的应用仍面临诸多限制，难以兼顾结构强度和抗腐蚀性。本研究选用TA1纯钛作为主体结构材料，设计并研制出一款整体厚度仅为0.3 mm的超薄钛基均热板（TIVC）。其中，吸液芯选用镍丝网基材，借助超快激光诱导高温等离子体实现原位沉积改性，在表面构筑粗糙多孔的微纳复合结构，大幅增强毛细抽吸与工质回流能力；同时，对刻蚀有导流沟槽的腔体内壁开展激光纹理化加工，构筑次级毛细功能结构，进一步优化液体铺展特性与相变传热效率。实验结果表明，相较于仅采用等离子体亲水化处理腔体的对照组，激光纹理化改性腔体的样品在抗重力工况下的传热性能提升了66.7%。器件整体采用激光密封焊接工艺完成气密封装，有效保障了超薄腔体的结构完整性与长期工作可靠性。在自然空气对流环境下，该超薄钛均热板在水平、顺重力、抗重力三种姿态下的极限传热功率分别可达5、6与5 W，工作过程中板面温度分布均匀，换热运行状态稳定。本研究为轻量化、耐腐蚀、高适配性的超薄均热板开发提供了新的设计思路与可行技术方案。更多还原

【Abstract】 Objective The continuous miniaturization and lightweighting of consumer electronic devices impose growing challenges on thermal management. Ultra-thin vapor chambers（UTVCs）, which rely on phase-change heat transfer and capillary-driven liquid circulation, emerge as high-performance planar heat spreaders. Nevertheless, conventional copper-based UTVCs present inherent limitations in scenarios demanding lightweight design and high structural reliability, including wearable devices, augmented reality（AR） glasses, and foldable electronics. Copper possesses a low strength-to-weight ratio and poor compatibility with infrared laser welding, restricting further miniaturization and reliable hermetic sealing. Although stainless-steel-based UTVCs deliver superior mechanical strength, they exhibit unsatisfactory chemical compatibility with water-based working fluids. In comparison, titanium features low density, high specific strength, excellent corrosion resistance, and favorable laser absorptivity, making it an attractive candidate structural material for ultra-thin vapor chambers. Titanium inherently shows limited surface wettability, and nickel wire meshes that are chemically compatible with the titanium-water system still suffer from insufficient capillary performance without hydrophilic modification, especially under anti-gravity conditions. Accordingly, this study adopts ultrafast laser technology to synergistically engineer the microstructures of both the wick and the chamber inner surface, aiming to develop ultra-thin titanium-based vapor chambers with enhanced capillary liquid backflow capability and highly reliable hermetic sealing performance.Methods A titanium UTVC with an overall thickness of 0.3 mm is designed and fabricated from commercially pure titanium（TA1）. The chamber consists of a chemically etched titanium bottom plate with microgrooved flow channels and a top plate with intermittently arranged support pillars to guarantee mechanical stability and vapor transportation. A double-layer nickel wire mesh acts as the wick structure and is modified via ultrafast-laser-induced high-temperature plasma in-situ deposition, forming a rough, porous hierarchical micro-nano surface to improve capillary performance. A two-step deposition strategy is adopted to achieve uniform modification on both sides of the mesh. The inner chamber surface is further processed by ultrafast laser texturing to construct secondary capillary channels composed of micropits and nanostructures. Surface morphology and wettability are systematically characterized. Capillary wicking tests are performed on nickel meshes with different mesh numbers（200, 250, and 300 mesh）, and the capillary performance parameter K/R_eff is evaluated based on the Washburn model. Finally, high-speed fiber laser welding is utilized to realize reliable hermetic sealing. Thermal performance is measured under natural convection in horizontal, gravity-assisted and antigravity orientations, and the influence of surface texturing and filling ratio is quantitatively analyzed.Results and Discussions Ultrafast laser plasma in-situ deposition successfully forms a three-dimensional porous micro – nano particle layer on the nickel wire mesh, significantly increasing surface roughness and surface energy and endowing the mesh with superhydrophilicity. Capillary rise experiments show that the 250 mesh nickel wire mesh delivers the highest wicking velocity and the largest K/R_eff value, achieving an optimal balance between capillary driving force and flow resistance. Laser texturing applied to the etched titanium chamber surface efficiently creates interconnected secondary microchannels. At an optimized repetition frequency of 400 kHz, the surface presents a well-connected rough hierarchical morphology and exhibits the fastest liquid spreading behavior. Compared with chambers treated only by plasma hydrophilization, laser-textured chambers possess distinctly enhanced liquid redistribution and replenishment capabilities. Thermal performance tests under anti-gravity conditions indicate that the laser-textured chamber achieves approximately 66.7% improvement in heat transfer performance over the non-textured one, which benefits from the formation of continuous liquid films and strengthened capillary-driven liquid backflow. The assembled ultra-thin titanium-based vapor chamber（TIVC） maintains stable operation and uniform temperature distribution. Under natural convection, its maximum heat transfer capacity reaches 5 W in the horizontal orientation, 6 W in the gravity-assisted orientation, and 5 W in the anti-gravity orientation, while the temperature difference between measuring points remains below 5 °C. Filling ratio optimization further improves thermal stability, particularly under anti-gravity conditions, where insufficient or excessive liquid loading easily causes premature dryout or vapor blockage. These results validate that synergistic microstructure engineering of the wick and chamber inner surface effectively overcomes the capillary performance limitations of ultra-thin titanium vapor chambers.Conclusions In this study, an ultra-thin titanium-based vapor chamber with an overall thickness of 0.3 mm is successfully fabricated via a synergistic strategy combining ultrafast-laser-induced plasma in-situ deposition and surface texturing. Multiscale microstructural modification of the nickel mesh wick and the inner surface of the titanium chamber greatly enhances capillary liquid backflow and anti-gravity heat transfer performance. The results reveal that ultrafast-laser-induced micro/nano porous structures endow the nickel mesh with stable superhydrophilicity. Among the tested meshes, the 250 mesh nickel wire mesh achieves an optimal balance between capillary driving force and flow resistance, and exhibits the highest capillary reflux capacity. Furthermore, laser texturing on the chamber inner surface constructs interconnected secondary microchannels, yielding an approximately 66.7% improvement in anti-gravity heat transfer performance compared with the untreated reference sample. Under natural convection, the prepared ultra-thin titanium vapor chamber delivers maximum heat transfer capacities of 5, 6, and 5 W in horizontal, gravity-assisted, and anti-gravity orientations respectively, with temperature differences kept below 5 °C, which demonstrates outstanding temperature uniformity and operational stability. Overall, this work provides a viable technical route for developing ultra-thin metal vapor chambers with lightweight configuration, high-reliability encapsulation, and efficient phase-change heat transfer performance.更多还原