Читать книгу Lead-Free Piezoelectric Materials - Jing-Feng Li - Страница 29

For decades, Pb(Zr,Ti)O₃ (PZT)‐based ceramics have been market‐dominating due to its excellent properties and flexibility in terms of compositional modifications. On the other hand, developing high‐performance lead‐free piezoelectric ceramics has been one of the most active materials research topics in the last decades. At present, a single replacement for PZT may not be available, but the abovementioned lead‐free systems are already applicable for some applications. Among them, KNN appears to be the most promising one for its well‐balanced combination of high piezoelectricity and Curie temperature. In addition, as shown in Chapter 3, KNN‐based ceramics can be co‐fired with base metals like nickel, which is a critical factor for the cost‐effective fabrication of multilayered piezoceramic actuators. Certainly, other systems also have certain advantages, such as large piezoelectric strains in BNT‐based ceramics and high Curie temperature in BiFeO₃‐based ceramics. However, all these known lead‐free materials are unlikely to be such an “all‐round player” that can be modified to exhibit different properties by changing doping elements as in PZT, so there still needs a further long way to develop lead‐free piezoceramics that are completely capable of replacing PZT‐based ceramics.