Study of Piezoelectric Actuation for Cross-Ply Laminates

Experimental and numerical methods are presented for piezoelectric actuation of thin deformed post-cure cross-ply carbon fiber composite laminates. During the fabrication process, the composite laminates are held under a press until the curing temperature is reached. After which, the press is released and the laminates are allowed to cool. During this cooling period the once flat composite laminates deform to one of the two cylindrical shapes. The curvature of the cross-ply post-cure cylindrical shape is symmetric and therefore the transverse displacement is measured using a FARO gage coordinate measuring machine (CMM). The snap through force studied here is generated by a macro-fiber composite patch (MFC), which is bonded to the deformed composite plate. Applying a voltage to the MFC patch induces a mechanical strain in the patch which is then transferred from the patch to the composite laminate causing it to snap through to an orthogonal cylindrical shape. After snap through, the second cylindrical shape is measured using the FARO gage CMM. The numerical post fabrication curvatures and piezoelectrically morphed curvatures compare well to the experimental data.