Defect-relevant piezoelectric and ferroelectric properties in LiCuTa3O9-doped K0.5Na0.5NbO3 lead-free piezoceramics

Textured Potassium Sodium Niobate Lead-Free Ceramics with High d33 and Qm for Meeting High-Power Applications

“…The electromechanical coupling factor k p and the mechanical quality factor Q m were calculated from the parameters ( f r : resonance frequency, f a : antiresonance frequency, C f : capacitance at 1 kHz, R z : resonance impedance) obtained using an impedance analyzer (Agilent 4294A, Hewlett-Packard, Palo Alto, CA) according to eqs. (1) and (2), , respectively. 1 k p 2 = f r 2.51 × false( f a − f r false) Q m = 1 2 π f r R z C f true{ 1 − ( f r f a ) 2 true} …”

Performance enhancement of soft‐PZT5 piezoelectric ceramics using poling technique

“…The piezoelectric constant d 33 , free dielectric permittivity ($$\varepsilon _{33}^T/{\varepsilon _0}$$) and dielectric loss (tan δ ), and X‐ray diffractometer measurements refer to the literature. 23 The electrical coupling coefficient ( k p ) and mechanical quality factor ( Q m ) were measured using an impedance analyzer and then calculated using the following equations: 24 $$\begin{equation} \frac{1}{{k_p^2}} = 0.395\frac{{{f_r}}}{{{f_a} - {f_r}}} + 0.574\end{equation}$$ $$\begin{equation} {Q_m} = \frac{1}{{2\pi {f_r}{R_z}{C_f}\left\{ {1 - \frac{{f_r^2}}{{f_a^2}}} \right\}}} \end{equation}$$where f r , f a , C f , and R z are the resonance frequency, anti‐resonance frequency, capacitance at 1 kHz, and resonance impedance, respectively.…”

“…The piezoelectric constant d 33 , free dielectric permittivity (𝜀 𝑇 33 ∕𝜀 0 ) and dielectric loss (tanδ), and X-ray diffractometer measurements refer to the literature. 23 The electrical coupling coefficient (k p ) and mechanical quality factor (Q m ) were measured using an impedance analyzer and then calculated using the following equations: 24 1 𝑘 2 𝑝 = 0.395 𝑓 𝑟 𝑓 𝑎 − 𝑓 𝑟 + 0.574…”