Microstructure, mechanical behavior and flow resistance of freeze-cast porous 3YSZ substrates for membrane applications

Freeze-cast porous 3YSZ with different porosities were characterized as mechanical load carrying supports for oxygen transport membrane applications. Porosity influence on mechanical properties, i.e. elastic modulus and fracture stresses was assessed with biaxial ring-on-ring bending tests. The flow resistance was characterized in terms of the pressure drop using different gases to reveal the effect of the porous support on the accessing of the inlet gas flow to the functional dense membrane layer. Both properties were discussed in terms of the influence of porosity and pore structure, and compared with the properties of porous 3YSZ produced via pressing and sintering.