DEVELOPING A VIRTUAL DAMAGE SENSOR USING A COUPLED ELECTRO-MECHANICAL FE MODEL OF A PIEZOELECTRIC MATERIAL

This article develops a finite element model coupling transient electric and dynamic mechanical fields for a piezoelectric material. The mechanical field incorporates finite deformation kinematics with continuum damage relations to account for change in mechanical and piezoelectric material properties with deformation-induced damage evolution. The main interest in the coupled mechanical-piezoelectric model with damage is to serve as a electric field-based virtual damage sensor. The coupled mechanical-piezoelectric (ME-PE) code is validated by comparing with analytical results and those from commercial software. An electric field-based damage indicator function is proposed and calibrated from data obtained through numerical solutions using the ME-PE code. The function relates the electric field difference for undamaged and damaged conditions to the damage parameter, its rate and mechanical and piezoelectric material properties. The virtual damage sensor is used to examine damage conditions in a stretchable piezoelectric serpentine conductor.