A new design for co-extrusion dies: Fabrication of multi-layer tubes to be used as solid oxide fuel cell

Solid oxide fuel cells attract growing attention as an environmentally friendly device that can produce electrical power. Many processing routes are available for fabrication of micro-tubular solid oxide fuel cells, among which extrusion can be considered as the most commonly used method. Recently, a co-extrusion process has been introduced, in which anode and electrolyte layers can be fabricated simultaneously, thus reducing the overall fabrication cost. In this study, a new die design for co-extrusion of ceramic tubes is introduced in which 5 different layers can be fabricated by a single processing step and can be used for fabrication of micro-tubular solid oxide fuel cells. Moreover, an integral model developed for pressure drop in different flow fields of the die. Summing up the pressure drops, the pressure drop in the whole process can be calculated. The SEM images show that the co-extrusion process can be performed successfully and the tube consists of 5 distinct layers.