Jiakang Langevin Ultrasonic Transducers

A sandwich piezoelectric transducer made up of metal blocks on both end faces of a piezoelectric ceramic disc is mostly used in the field of power ultrasonic and underwater acoustics applications.

Lang Zhiwan, a French physicist, proposed the transducer for this structure, which is also known as the Langevin transducer.

The advantage of this transducer structure is that it makes use of both the longitudinal effect of the piezoelectric ceramic vibrator and the lower resonance frequency. On the other hand, due to the properties of the piezoelectric ceramic itself, tensile strength is poor at high power. It is prone to cracking in operating conditions. Prestressing is applied to the piezoelectric ceramic disc using metal blocks and pre-stressed bolts, ensuring that the disc remains compressed under strong vibration and preventing fracture of the piezoelectric ceramic sheet.