In the development of piezoelectric ultrasonic transduc […]
In the development of piezoelectric ultrasonic transducers, piezoelectric materials Performance improvement is the key. According to reports, relevant units at home and abroad have developed A new type of piezoelectric single crystal material (AB; CAD and AE; CAD) The piezoelectric constant is the existing traditional piezoelectric material (such as lead zirconate titanate material) Material) several times or even dozens of times, but the working frequency of this material The limit needs to be further increased. It can be expected that once this material is Change, the power capacity and vibration displacement of the transducer will be revolutionary In addition, most of the existing piezoelectric ceramic materials are used Lead-based piezoelectric materials, but due to the implementation of the international environmental protection law, The development of lead-free piezoelectric materials has reached a new level. There have been quite a lot of research reports on lead-free piezoelectric ceramics in China.
Channel, but it can be used in power ultrasonic transducers and can be combined with lead zirconate titanate ceramics Cheap lead-free piezoelectric ceramic materials comparable to porcelain materials are actually not exist. Magnetostrictive transducers are based on certain ferromagnetic materials and ceramic materials A kind of machine-to-sound conversion made by the magnetostrictive effect of the material Acoustic devices (see picture "), traditional magnetostrictive materials include nickel, aluminum and iron Alloys, iron-cobalt-vanadium alloys, iron-cobalt alloys and ferrite materials, etc., and Compared with piezoelectric ultrasonic transducer, made of traditional magnetostrictive material.
The application range of the magnetostrictive transducer has been very small, causing this The reason is that the electromechanical conversion efficiency of the magnetostrictive transducer is relatively low. Low, and its excitation circuit is more complicated, however, with materials science and technology Development and the successful development of rare earth giant magnetostrictive materials, magnetostrictive The telescopic transducer has received a certain amount of attention again & it is expected that in the near future, Li High-power transducers made of rare earth giant magnetostrictive materials will be Acoustic technology obtains large-scale application.