Activation of ferroelectric implant ceramics by corona discharge poling
Magnus Rotan, Mikalai Zhuk, Julia Glaum
Abstract
Ferroelectric ceramics show great potential for medical implants to augment bone regeneration and improve implant fixation. To induce an overall piezoelectric response prior to implantation, a clean, contact-less and non-line-of-sight electrical poling method is preferred to allow poling of arbitrarily structured scaffolds without the need for electrodes or insulating liquids. A feasibility study was conducted on the use of corona discharge, which is a contact-less poling method operating in air, to piezoelectrically activate (Ba,Ca)(Zr,Ti)O3 (BCZT), (K,Na)NbO3 (KNN) and commercial Pb(Zr,Ti)O3 (PZT) ceramics. While both PZT and BCZT are readily poled by the corona technique, KNN requires a high electric field and an extended poling period to activate its piezoelectric potential. Comparing the poling characteristics of samples with and without electrodes revealed that the same degree of poling can be achieved. These results highlight that corona discharge is a feasible method to pole piezoelectric ceramics intended for biomedical applications.