Mechanical Properties and Plastic Behaviour Mechanism Induced by Nanoindentation Technique of YSZ and GDC Materials used as Electrolytes in Fuel Cells Devices

In this study, mechanical characterization at nanometric scale was carried out for different ceramic materials (Yttrium–Stabilized Zirconium, YSZ, and Gadolinium–doped Cerium, GDC) both widely employed as electrolytes in Solid Oxide Fuel Cells (SOFCs). The applied load (P)–displacement (h) curves, and the energy data (total, plastic, and elastic energy) were analysed to evaluate the minimum work necessary to produce plastic deformation. The different mechanical properties were calculated by the Oliver and Pharr approach, and the work of indentation method. As a result, it was determined that the hardness for YSZ is higher than for GDC materials, and the Young’s modulus for both studied materials is similar. Finally, fracture behaviour of each of the materials during indentation (chipping, cracks, and other mechanisms) was also discussed in detail from the residual imprints observed with Atomic Force Microscopy(AFM).