Effect of diffusion bonded wick structure on thermal performance of heat pipe

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.