Fabrication of copper-based microchannel devices and analysis of their flow and heat transfer characteristics

Abstract

Metal-based microchannel heat exchangers (MHEs) offer potential solutions to high heat flux removal applications, such as cooling of high-performance microelectronic and energy-efficient lighting modules. Efficient fabrication of metal-based MHEs and quantitative flow and heat transfer measurements on them are critical for establishing the economic and technical feasibility of such devices. In this paper, all-Cu MHE prototypes were fabricated. Results of flow and heat transfer testing made on these Cu-based MHE prototypes are reported. Efficient fabrication of Cu-based high-aspect-ratio microscale structures (HARMSs) was achieved through direct molding replication using surface-engineered metallic mold inserts. Replicated Cu HARMSs were assembled through solid-state bonding to form all-Cu MHE prototypes. Flow and heat transfer testing of the Cu MHE prototypes was conducted to determine the average rate of heat transfer from the solid Cu body to water flowing within the enclosed microchannel array. Experimentally observed flow and heat transfer data are analyzed and shown to agree with known macroscale correlations once surface roughness and entrance length effects are taken into account.

Investigation of the Corrosion Behavior of Atomic Layer Deposited Al2O3/TiO2 Nanolaminate Thin Films on Copper in 0.1 M NaCl

“…Copper is ubiquitous in numerous industries due to its relatively low cost coupled with its malleability and high electrical and thermal conductivities. It has uses in everything from residential and commercial plumbing [ 1 , 2 , 3 , 4 ] and electrical wiring to industrial heat exchangers [ 5 , 6 , 7 ] and high-powered electronics [ 8 , 9 , 10 , 11 ]. Copper possesses adequate aqueous corrosion resistance due to the formation of a semi-protective native oxide film.…”

Bonding of Cu-based high aspect ratio microscale structures with Sn intermediate layers

“…8b. Such all-Cu, enclosed, microchannel structures can serve as building blocks for metal-based microchannel fluidic devices, such as MHEs (Mei et al , 2009a. Figure 9a shows three parts to be assembled: a pre-bonded, all-Cu, enclosed microchannel structure together with two Cu fluidic adaptor pieces.…”

“…Since then, microchannel heat exchangers (MHEs) have become a leading contender for solving high heat flux removal problems (Mudawar 2001). Although most experimental heat transfer investigations have been conducted on Si-based microchannel devices (Kohl et al 2005), metal-based MHEs, with higher thermal conductivities and increased mechanical robustness, offer potential performance improvements over Si-based counterparts (Mei et al 2009a). Elemental Cu, with room-temperature thermal conductivity lower than only diamond and Ag, is one of the most important materials for heat exchange applications.…”

Fabrication, assembly and heat transfer testing of low-profile copper-based microchannel heat exchangers

“…In contrast, metal-based MHEs offer better heat transfer performance by taking advantage of the high thermal conductivities of metals and the high rates of liquid-solid convective heat transfer within microchannels [10,11]. In this paper, we report on results of fabrication and bonding of low-profile Cu MHEs with varying geometric dimensions.…”