Sol-gel composite film fabrication by paint stencil printing

Piezoelectric ceramics by sol-gel composites could be useful as ultrasonic transducers in real industry fields. For sol-gel composite film fabrication, spray coating technique has been used frequently because of adaptability for various substrates. However, spray coating method requires multiple spray coating processes and heating processes and it is an anxious issue, particularly for on-site fabrication under controlled area. Paint stencil printing has been developed in order to solve the above issue because this method enables to fabricate thick sol-gel composite films by one coating process. In this study, PbTiO₃ (PT)/ Pb(Zr,Ti)O₃ (PZT) films were fabricated by paint stencil printing and spray coating technique, and thermal cycle test between room temperature and 300°C was operated for both samples in order to compare ultrasonic performance and adhesive strength. As a result, sensitivity and signal-to-noise-ratio (SNR) of ultrasonic response by stencil printing were equivalent with those by spray technique. Therefore, PT/PZT films fabricated by paint stencil printing could be a good candidate as ultrasonic transducers for non-destructive testing (NDT) from room temperature to 300 °C.