Abstract
Elastic properties of 20 and 40 µm thick deposits of yttria fully stabilized zirconia (YSZ), fabricated by vacuum plasma spraying (VPS) and air plasma spraying (APS) with modified injection system were investigated at room temperature by nanoindentation, and 4 point flexion test and at 800°C by 4 point bend test. The data was correlated with structural analysis of different YSZ deposits. At room temperature, E values of VPS YSZ deposit decreased from 237 ± 6 to 105 ± 5 GPa on increasing nanoindentation load from 1 mN to 450 mN. The results indicated change from intrinsic to defect-dependent E values with increasing load. Despite lower porosity of VPS deposit (6 ± 1%) compared to that of APS (24 ± 1%), E values, measured by flexion test at room temperature and at 800°C, of former were 35 ± 1 and 16 ± 1 and of latter were 55 ± 1 and 18 ± 1 GPa respectively. The interlamellar sliding, parallel to applied load, was considered as prime reason of lower rigidity of deposits.
