Local elastic response of individual grains in lead-free Nb-doped Bi4Ti3O12 piezoelectric ceramics

The local elastic response of individual grains in lead-free Nb-doped Bi4Ti3O12 piezoelectric ceramics have been examined by atomic force microscopy in the acoustic mode. Subsurface features with different elasticity down to 60 nm are imaged from the cantilever deflection vibration at a modulation frequency much lower than the cantilever resonance. Local elastic regions parallel and perpendicular to the long axis of the plate-like grains are found in the Bi4Ti3O12 piezoelectric ceramics, which are most likely a result of the crystal structure arrangement undergone in the grain growth of the Nb-doped Bi4Ti3O12 piezoelectric ceramics during sintering. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)