小型金属粉末烧结吸液芯圆热管(简称烧结热管)是一种提高高热流密度电子元器件散热性的高热导率元件，而烧结工艺是决定烧结热管质量的关键。根据烧结热管传热特性优化热管吸液芯的结构及工艺，提出制造热管烧结吸液芯的四阶段固相烧结工艺，讨论烧结工艺参数：烧结温度、烧结时间、烧结气氛和烧结位置。结果表明：当烧结吸液芯厚度为0.45 mm，烧结时间为3 h时，159μm铜粉的烧结吸液芯合理的烧结温度是950°C，81μm和38μm铜粉的烧结吸液芯合理的烧结温度为900°C。当铜粉粒径为159μm，烧结温度为950°C时，0.45和0.6 mm吸液芯厚度合理的烧结时间为3 h，而0.75 mm吸液芯厚度合理的烧结时间为1 h。在烧结过程中H2与CuO还原反应能够在铜粉表面形成龟裂纹，而龟裂纹可作为二次结构。水平位置烧结能有效地避免烧结吸液芯与铜管内壁之间产生间隙。%Miniature cylindrical metal powder sintered wick heat pipe (sintered heat pipe) is an ideal component with super-high thermal efficiency for high heat flux electronics cooling. The sintering process for sintered wick is important for its quality. The sintering process was optimally designed based on the equation of the heat transfer limit of sintered heat pipe. Four-step sintering process was proposed to fabricate sintered wick. The sintering parameters including sintering temperature, sintering time, sintering atmosphere and sintering position were discussed. The experimental results showed that the proper sintering temperature was 950 °C for Cu powder of 159μm and 900 °C for Cu powders of 81 and 38 μm, respectively, while the wick thickness was 0.45 mm and sintering time was 3 h. The optimized sintering time was 3 h for 0.45 and 0.6 mm wick thickness and 1 h for 0.75 mm wick thickness, respectively, when copper powder diameter was 159μm and sintering temperature was 950 °C. Redox reduction reaction between H2 and CuO during sintering could produce segmentation cracks in Cu powders as a second structure. Sintering at vertical position can effectively avoid the generation of gap between wick and the inner wall of pipe.
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