IEEE Trans Ultrason Ferroelectr Freq Control. 2010 Sep;57(9):2103-10. doi: 10.1109/TUFFC.2010.1659.
Piezoelectric films have been deposited by a sol-gel spray technique onto 75-μm-thick titanium and stainless steel (SS) membranes and have been fabricated into flexible ultrasonic transducers (FUTs). FUTs using titanium membranes were glued and those using SS membranes brazed onto steel pipes, procedures that serve as on-site installation techniques for the purpose of offering continuous thickness monitoring capabilities at up to 490 °C. At 150 °C, the thickness measurement accuracy of a pipe with an outer diameter of 26.6 mm and a wall thickness of 2.5 mm was estimated to be 26 μm and the center frequency of the FUT was 10.8 MHz. It is demonstrated that the frequency bandwidth of the FUTs and SNR of signals using glue or brazing materials as high-temperature couplant for FUTs are sufficient to inspect the steel pipes even with a 2.5 mm wall thickness.
压电薄膜通过溶胶-凝胶喷涂技术沉积在 75μm 厚的钛和不锈钢（SS）膜上，并被制成柔性超声换能器（FUT）。使用钛膜的 FUT 通过胶合，而使用 SS 膜的 FUT 通过钎焊连接到钢管上，这些工艺是现场安装技术，旨在提供高达 490°C 的连续厚度监测能力。在 150°C 下，对 26.6mm 外径和 2.5mm 壁厚的管道的厚度测量精度估计为 26μm，FUT 的中心频率为 10.8MHz。结果表明，即使使用 2.5mm 壁厚的 FUT，使用胶水或钎焊材料作为 FUT 的高温偶联剂的 FUT 的频率带宽和信号 SNR 足以检查钢管。
