Fabricated Process And Heat Transfer Performance Analysis Of Copper Vapor Chamber

With the development of optoelectronic field to high performance and high integration direction, the cooling of electronic components has become an increasingly prominent issue. And use of gas-liquid phase change principle to transfer heat has become the preferred way to solve the heat problem in the present. Vapor Chamber(VC) is a heat transfer plate device which utilizes the gas-liquid phase change principle to transfer heat, and it is mainly composed of two shell plates, wick, the working fluid and the filling tube. The mainly research works are summarized as follows:Designed two kinds of VCs, copper foam based VCs and copper powder sintered VCs. The copper powder sintered VCs are designed with snap down wick structures. The deformation problem is solved by using copper solid columns and wick columns. And the manufacturing process of VCs is studied to determine the process parameters.The porosities of various wick structures are measured. And the internal pores diameter, the particles diameter and bonding situation of the wicks are observed by use of Scanning Electron Microscope(SEM). An air-cooled testing device was designed to testing the VC’ temperature uniformity of the evaporation and condensation, the thermal resistance and the maximum transfer power.Five groups of copper foam based VCs with different filling rates(50%, 90%, 120%, 150% and 190%) are produced. The effects of different liquid filling rates on the VCs’ heat transfer performance are studied. The experiment shows that if the VC’ liquid filling rate is too low, it would result in an uneven temperature distribution, but excessive filled liquid would cause a deteriorated startup performance. The temperature uniformity of NO. B3 VC(90%) is the best and the thermal resistance of NO. C4 VC(120%) is the smallest.Four types of copper powder sintered VCs are made by different average diameters copper powder(265 ± 85μm, 143 ± 37μm, 90 ± 15μm and 66 ± 9μm). The effects of the copper powder size on the heat transfer performance of the VCs are studied. The experiment shows that when the heat source power is up to a certain value, the heat performance of the VC with small size copper powder is better than that with the larger size, and the temperature uniformity of NO. F3 VC(90±15μm) is the best, and the thermal resistance of No. F4 VC(66 ± 9μm) is the smallest.A solid copper plate with the same size of experiment VC is used as the reference. The effects of heat flux density on the thermal performance of solid copper plate and VCs are investigated. The results show that VCs’ performance is much better than the solid copper plate. With high heat flux density, copper foam based VCs have better temperature uniformity, while the copper powder sintered VCs’ have smaller thermal resistance.