Non-Classical Continuum Model for Nano-Scaled Piezoelectric Films and Its Applications

Owing to the discovery of carbon nanotubes and the fast advancement in nanomechanical technology, micro- and/or nano-devices are of increasingly great demand in the forthcoming near future. This project proposes to investigate the electromechanical characteristics of nano-scaled piezoelectric films and its potential applications. Because the surface-to-bulk ratio for nano-structures increases markedly at minute dimensions, the size-dependent surface stress effects are very significant. Hence, (i) a non-classical nanomechanical model will be developed based on the theory of surface piezoelectricity. A formalism of non-classical plate theory for nano-scaled piezoelectric and/or functionally graded piezoelectric films will then be established. (ii) The project will also endeavour the size-dependent elastic-electric coupling behaviour, including bending, vibration, buckling and its critical applied voltage, because these properties are of paramount importance for efficient designing of nano-structures and in-service performance evaluation. (iii) Subsequently the adhesion instability will be examined because to analyze the failure modes of nano-scaled film devices.