Complex Electrophysical Parameters of Lead-Free Piezoelectric Ceramics Based on Lithium-Sodium Niobates Solid Solutions

摘要

Complex studies of the properties of lead-free ferroelectric ceramics based on solid solutions of the (Na, Li)NbO_3 system have been carried out. Experimental samples of piezoceramics were fabricated by the hot-pressing method. Measurements of complex elastic, dielectric and piezoelectric parameters, as well as microstructural studies of experimental samples were performed. A complete set of complex elastic, dielectric, and piezoelectric parameters of lead-free ferroelectric ceramics Na_(0.86625)Li_(0.12375)Sr_(0.01)Nb_(0.988)Al_(0.01)O_(2.995) was obtained. The frequency dependences of complex parameters of experimental samples in the frequency range up to 100 MHz were studied. It was shown that the Na_0.86625Li_0.12375Sr_(0.01)Nb_(0.988)Al_(0.01)O_(2.995) lead-free piezoceramics are characterized by a low attenuation of ultrasonic waves and the absence of dispersion over a wide frequency range and can be used in high-frequency ultrasonic transducers for medical equipment and non-destructive testing.