Abstract：
High-temperature ultrasonic transducer (HTUT) is essential for non-destructive testing (NDT) in harsh environments. In this paper, a HTUT based on BiScO3-PbTiO3 (BS-PT) piezoelectric ceramics was developed, and the effect of different backing layers on its bandwidth were analyzed. The HTUT demonstrates a broad bandwidth and excellent thermal stability with operation temperature up to 400 °C. By using a 10 mm thick porous alumina backing layer, the HTUT achieves a broad -6 dB bandwidth of 100 %, which is about 4 times superior to the transducer with an air backing layer. The center frequency (fc) of the HTUT remains stable with fluctuations of less than 10 % across the temperature range from room temperature to 400 °C. The HTUT successfully detected simulated defects in pulse-echo mode for NDT over 200 °C. This research not only advances high-temperature ultrasonic transducer technology but also expands the NDT applications in harsh environmental conditions.
摘要：
高温超声换能器（HTUT）对于恶劣环境下的无损检测（NDT）至关重要。在本文中,开发了一种基于BiScO3-PbTiO3（BS-PT）压电陶瓷的HTUT，分析了不同背衬层对其带宽的影响。HTUT具有宽的带宽和出色的热稳定性，工作温度高达400°C。通过使用10毫米厚的多孔氧化铝背衬层，HTUT实现了100%的宽-6dB带宽，这是大约4倍优于换能器与空气背衬层。HTUT的中心频率(fc)在从室温到400°C的温度范围内保持稳定，波动小于10%。HTUT在200°C以上的NDT中以脉冲回波模式成功检测到模拟缺陷。这项研究不仅促进了高温超声换能器技术的发展，而且还扩展了NDT在恶劣环境条件下的应用。
