LEAD-FREE PIEZOELECTRIC CERAMIC MATERIAL Russian patent published in 2020 - IPC C04B35/495 

FIELD: piezoelectric engineering.

SUBSTANCE: invention relates to piezoelectric engineering and can be used for creation of high-frequency piezoelectric transducers operating in wide temperature range (20–800) °C and frequencies, in particular, used in ultrasonic flaw detection, to measure vibration and impact of heat loaded structures subjected to dynamic effects. Lead-free piezoelectric ceramic material, which includes Li₂O and Nb₂O₅, additionally contains oxide of element from group, wt. %: Zn²⁺, Mg²⁺, La³⁺, Sc³⁺, Sn⁴⁺, Zr⁴⁺ or W⁶⁺, and its composition corresponds to formula xLi₂O-yNb₂O₅-AⁿO_n/2, where x + y + z = 100, wherein 9.33 ≤ x ≤ 9.35, 83.02 ≤ y ≤ 83.21, 7.44 ≤ z ≤ 7.65, Aⁿ – oxide of element with even valence n from group Zn²⁺, Mg²⁺, Sn⁴⁺, Zr⁴⁺, W⁶⁺, or xLi₂O-yNb₂O₅-zA₂O₃, where x + y + z = 100, wherein 10.09 ≤ x ≤ 10.10, 89.74 ≤ y ≤ 89.81, 0.09 ≤ z ≤ 0.17, A - La³⁺, Sc³⁺.

EFFECT: higher specific volume electric resistance ρ_v, low dielectric loss tangent tgδ while maintaining low values of relative permittivity εε₃₃^T/ε₀ and sufficiently high values of piezoelectric module d₃₃.

1 cl, 3 tbl