Abstract: Copper foils with etched axial grooves were diffusion bonded to carry out laminated object manufacturing (LOM) of a wick and integral structure for flat heat pipe. The influences of groove width, heating power and cooling mode on thermal performance of the heat pipe were studied experimentally. The results indicate that LOM structure by diffusion bonding is applicable in manufacturing flat heat pipe. Heat pipe with the groove width of 0.4 mm worked well during the whole experiments, and the best performance was presented under the heating power of 40 W, put horizontally, forced air cooling during heating, with the equivalent thermal conductivity reaching 2552.2 W·m^-1·K^-1, which is 6.7 times that of copper. Smaller grooves formed during diffusion bonding can help liquid reflow, which enhances the thermal performance of the heat pipe.

Key words: diffusion bonding, manufacture, wick, micro channel, flat heat pipe, heat transfer, equivalent thermal conductivity

摘要： 利用扩散焊分层实体制造技术对蚀刻紫铜薄片进行焊接，完成吸液芯结构（微通道）的制造以及平板热管整体结构的装配。通过系统研究分析了槽道宽度、加热功率以及冷却方式对热管性能的影响。结果表明，该方法能较好地实现热管吸液芯结构以及整体结构的制造；试验过程中槽道宽度为0.4 mm的热管性能最优，在加热功率为40 W、水平放置、加热过程伴随风冷的试验条件下，其最大当量热导率能达2552.2 W·m^-1·K^-1，为紫铜的6.7倍。采用扩散焊分层实体制造的方法可以在槽道中形成很多小槽道，有利于液体工质的回流，从而提高热管的导热性能。

关键词: 扩散焊, 制造, 吸液芯, 微通道, 平板热管, 传热, 当量热导率