Electrical Conductivity Behaviour of Ferritic Steel Interconnect in Function of Spinel Composition, Electrode Material and Thermal Cycles

摘要

Conductivity of interconnects has been measured in function of different parameters. Two ferritic stainless steel grades were used, Crofer 22H and 22APU. Two different spinels composition were deposited, CuMn_2O_4 and Cu_(1.35)Mn_(1.65)O_4. Their thicknesses were varied from 4 to 16 μm to observe the influence on conductivity and its evolution over time. Measurements were done with direct contact between spinel coatings or by interposing an electrode material. For this purpose, LSC (La_(0.5)Sr_(0.5)CoO_3) or LSCF (La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_3) were directly screen printed on the spinel layer. All these different layers (Cu_xMn_yO4, LSC, LSCF) were deposited on small Crofer coupons (40x20x0.3 mm) and M_grid. Experiments were performed under oxidizing atmosphere at 800°C under air flow during hundreds of hours. Several thermal cycles were done to assess the stability of the coatings.