Lead-free piezoelectric ceramics are applications in piezoelectric transducers, accelerometers and buzzers. Two new types of lead-free piezoelectric ceramic systems have been successfully developed: sodium bismuth titanate-based and potassium sodium niobate-based new lead-free piezoelectric ceramic systems. Sodium bismuth titanate-based lead-free piezoelectric ceramics have piezoelectric characteristics such as high Kt, low Kp, small dielectric constant and bulk density, and moderate Qm; Alkali metal niobate lead-free piezoelectric ceramics have the unique advantages of making narrow pulse probes and high-resolution probes, and can replace the past PZT piezoelectric materials. Currently, they have been put into production in small batches on the production line and provided to domestic manufacturers. Transducer used in ultrasonic thickness measurement, ranging, industrial flaw detection and medical diagnosis.