A Review of Manufacturing Processes for Microchannel Heat Exchanger Fabrication

This paper provides a summary of the types of manufacturing processes currently being used in the fabrication of micro heat exchangers with the main focus on passages with hydraulic diameter of less than 200 micrometers. The following manufacturing processes are reviewed: LIGA, Chemical Etching, Stereolithography, and micro-machining. A comparison of different techniques related to tolerances, material compatibility, and ease of manufacturing is given. Processes capable of high volume fabrication are highlighted.