The carbon wire bundle's constructing as a capillary wick in the flat thin heat pipe

Flat plate heat pipe is required to be thin to apply 3D electronic package, which leads to declining heat transfer rate. Many studies enhance thermal performance by using various groove shapes, screen mesh, and mixed structures as wick. Nevertheless, these studies have not generated remarkable results. In the present study, we utilized carbon wire wick structure to improve the heat transfer rate of flat thin heat pipe (FTHP). The fabricated flat heat pipe in this study uses an aluminum container with 2 mm thickness and 12 channels to width direction via extrusion. The cross section of the aluminum container is designed as a groove wick structure at one side of the channel; a carbon wire is inserted to the other side. The carbon wire diameter is 7 µm, and the sharp edges made by carbon wires can contribute to capillary force creation. The 1 k carbon wire consists of a thousand carbon filaments. If the FTHP with carbon wire wick is developed, a valuable thermal solution with light weight, high thermal performance, thin thickness, and large contact area can be offered for electronic and telecommunication thermal management field. We developed a process for carbon wire attachment to the aluminum container. We bent both ends of an aluminum container, attached a carbon wire to the aluminum container, and cut an aluminum container. The carbon wire goes through the vacuum and seals the aluminum container. We fabricated FTHP with four kinds of carbon wires (3 k, 5 k, 7 k, and 10 k) to evaluate heat pipe performance. Result showed that the 5 k carbon wire wick heat pipe showed the highest isothermal performance. The 5 k carbon wire wick heat pipe recorded a lower temperature difference between evaporator and condenser of about 8.7%, 55.6%, and 3 times contrast the 3 k, 7 k, and 10 k carbon wire wick heat pipe. The carbon wire wick FTHP showed a lower thermal resistance and higher heat transfer than the groove wick FTHP.