Hot-Pressing Sintering Boosts High-Power Performance of PZT-Based Piezoelectric Ceramics: Tsinghua, BUPT, and BJUT Report in Nature Communications

Release time：

2025-11-14

Piezoelectric ceramics, serving as key functional materials for actuation and sensing, are widely used in advanced systems including ultrasonic medicine, precision industrial machining, marine acoustic detection, and energy conversion.Conventional characterizations are typically conducted under small-signal conditions. However, high-power operation is often accompanied by significantly enhanced electromechanical and thermomechanical coupling, leading to degradation of the mechanical quality factor, heat accumulation, and fatigue damage, which ultimately limits efficiency and reliability.For decades, fabricating piezoelectric ceramics that maintain high performance and stability under high-power conditions, while elucidating their underlying mechanisms, has remained a persistent challenge for both academia and industry.

Recently, a research team from the School of Materials Science at Tsinghua University has made significant progress in optimizing the high-power performance of lead zirconate titanate (PZT)-based piezoelectric ceramics.The team employed an inert hot-pressing process, lowering the sintering temperature from 1175 °C to 900 °C. Under these conditions of reduced temperature and shorter duration, the application of external pressure yielded dense, fine-grained, and structurally stable PZT-based piezoelectric ceramics.This study systematically revealed the underlying mechanism for enhanced high-power performance, achieving significant improvements in key metrics including maximum vibration velocity and mechanical quality factor.

The study demonstrates that the hot-pressing process significantly improved the material's microstructure.As shown in Fig. 1, the hot-pressed PZT ceramic (HP-PZT) exhibited significantly increased density, refined grains, a dominant tetragonal phase, and improved structural stability compared to conventionally sintered PZT (CS-PZT).Temperature-dependent Raman spectroscopy and dielectric temperature spectra revealed that HP-PZT maintains stable dielectric and ferroelectric properties at elevated temperatures (Fig. 2), demonstrating excellent thermal stability and resistance to failure. Under high-power driving conditions, HP-PZT showed significant performance enhancements: the maximum vibration velocity reached 2.5 m/s (compared to 1.7 m/s for CS-PZT); when operating at 1.0 m/s vibration velocity, its mechanical quality factor stability was markedly superior to conventional samples (Fig. 3).These results demonstrate that the hot-pressing process has significantly enhanced both energy conversion efficiency and high-power stability.Furthermore, the research team employed piezoelectric force microscopy (PFM) and X-ray photoelectron spectroscopy (XPS) to reveal the interaction mechanism between oxygen vacancies and domain walls (Fig. 4): Hot-pressing induced oxygen vacancies exert a pinning effect on domain walls under high electric fields, inhibiting irreversible domain motion. Combined with the internal stress field introduced by hot-pressing, these factors constitute the key source of high-power stability.

This study not only proposes a new mechanism for enhancing the high-power performance of piezoelectric ceramics, but also provides novel insights for optimizing the processing of related materials.Looking ahead, high-performance PZT ceramics based on hot-pressing technology are expected to find broader applications in ultrasonic medical devices, high-intensity sonar systems, and piezoelectric energy conversion fields.

These findings have recently been published in the renowned international journal Nature Communications under the title "High-power performance enhancement in PZT-based piezoceramics via hot-pressing".Wanting Cao (jointly trained at Tsinghua University) from Beijing University of Posts and Telecommunications is the first author. The corresponding authors are Ze Xu (Postdoctoral Researcher, Tsinghua University), Mupeng Zheng (Associate Researcher, Beijing University of Technology), and Ke Bi (Professor, Beijing University of Posts and Telecommunications).This work was supported by the National Natural Science Foundation of China, Beijing Natural Science Foundation, and China Postdoctoral Science Foundation.