Evaluation of Different Routes for Manufacturing of Micro Process Devices

Micro process devices offer a high surface-to volume ratio, e.g. facilitating high amounts of heat transfer. By this, strongly exothermic chemical reactions may be transferred from batch to continuous processes, reaching higher product yield and decreasing by-products. For manufacturing of micro process devices, microstructuring and joining of the apparatuses accounts for the overwhelming part of the cost. Various technologies can be used for microstructuring. They have certain constraints, advantages and disadvantages, which should be considered by the designer in advance. Due to small wall thickness between reaction and cooling passages, and for reasons of strength and corrosion resistance, additional materials, such as those common in brazing, should be avoided. Thus, mainly diffusion bonding and laser welding are applicable for joining. Again, these technologies has certain constraints, advantages and disadvantages, which may interact with microstructuring technologies. Experience has shown that the selection of suitable methods by the designer determines success or failure of manufacturing of micro process devices. For this reason, in this publication special features of the above-mentioned technologies and dependencies are discussed and illustrated by several practical examples.