The thermoplastic coextrusion process was used to fabricate YSZ/Ni-YSZ bi-layered composites. In this method, an initial feedrod was prepared by assembling YSZ and NiO-YSZ thermoplastic compounds to produce a monolithic body with a cross-section of 24 rum x 24 mm and then coextruded through various orifices having dimensions of 24 x 2, 1 and 0.6 mm at 120 degrees C. This simple process produced thin plates with a remarkable reduction in thickness, while preserving the YSZ:NiO-YSZ thickness ratio of 1:39. After binder removal, the samples were co-fired at 1350 degrees C for 3 h in air, followed by reduction at temperatures ranging from 700 to 900 degrees C for 5 h in an Ar-5% H, atmosphere. Using this method, it was possible to fabricate a YSZ/Ni-YSZ bi-layered composite without any noticeable defects, in which a 11-[mu m thick dense YSZ layer was coated onto a 400-mu m thick Ni-YSZ cermet. Furthermore, the fabricated samples showed reasonable electrical conductivities, thus rendering them suitable for use as the basic components of planar solid oxide fuel cells (SOFCs). (c) 2007 Elsevier B.V. All rights reserved.