**Abstract**

This chapter presents the investigation of fabrication and the physical properties of the Pb(Zr1−xTix)O3-Pb(Zn1/3Nb2/3)O3-Pb(Mn1/3Nb2/3)O3 multicomponent ceramics. The multicomponent *y*Pb(Zr1−xTix)O3-(0.925 − *y*)Pb(Zn1/3Nb2/3)O3- 0.075Pb(Mn1/3Nb2/3)O3 (PZT-PZN-PMnN) ceramics were synthesized by conventional solid-state reaction method (MO) combined with the B-site oxide mixing technique (BO). Research results show that the electrical properties of PZT-PZN-PMnN ceramics are optimal at a PZT content of 0.8 mol and Zr/Ti ratio of 48/52. At these contents, the ceramics have the following optimal properties: electromechanical coupling factor, *k*p = 0.62 and *k*t = 0.51; piezoelectric constant (*d*31) of 130 pC/N; mechanical quality factor (*Q*m) of 1112; dielectric loss (tan *δ*) of 0.005; high remanent polarization (*P*r) of 30.4 μC.cm−2; and low coercive field (*E*C) of 6.2 kV. cm−1. Investigation of the domain structure of the two ferroelectric phases (tetragonal and rhombohedral) in the ZnO-doped PZT-PZN-PMnN with compositions at near the morphotropic phase boundary is described as follows: the 90 and 180° domains exist in the tetragonal phase, while the 71, 109, and 90° domains are located in the rhombohedral phase, and the widths of these domains were about 100 nm. Besides, the ceramics exhibited excellent temperature stability, which makes them a promising material for high-intensity ultrasound applications.

**Keywords:** ceramics, the multicomponent ceramics, PZT-PZN-PMnN, ZnO nanoparticles, the ultrasonic transducers
