Manufacturing and testing of the sintered miniature loop heat pipe

In recent years, the high-power electronic devices cause the increasing demand of heat dissipation. Loop heat pipe (LHP), which possesses the advantages including high transfer capacity, long transport distance, self-priming, and active control, has a great potential for electronic cooling. However, with the miniaturizing of a LHP for electronic cooling, its performance will become more important to the capillary structure (wick) in the evaporator. The purpose of this study is to investigate the effect of the parameters of the metal sintering capillary structure by changing the sintering temperature (500~700°C) and sintering time (90~180mins) in the LHP. The results showed that there existed a better combination of manufacturing parameters by which the performance of the LHP would achieve a fine effect. According to an actual demand for electronic cooling, a miniature LHP was fabricated with the evaporator outer diameter of 15.5mm and the evaporator length of 65mm. The testing results showed that, at the allowable working temperature of 85°C, the maximum heat transfer capacity was up to 300 W and the thermal resistance was 0.29°C/W.