Nonlinear Behavior and High-Power Properties of (Bi,Na,Ba)TiO₃ and (Sr,Ca)₂NaNb₅O₁₅ Piezoelectric Ceramics

Abstract

The nonlinear behaviors and high-power properties of two lead-free piezoelectric ceramics – (Bi1/2Na1/2)0.85Ba0.15Ti0.98Mn0.02O3 (BNBTM) and Sr1.9Ca0.1NaNb5O15 (SCNN) – were clarified by comparison of their mechanical characteristics using the continuous driving method. BNBTM ceramics exhibited jump phenomena with constant-voltage driving that were similar to those found in Pb(Zr,Ti)O3-based (PZT) ceramics. The jump phenomena of SCNN ceramics produced mirror-reversed images relative to those of BNBTM ceramics. Their nonlinear behaviors were caused by the soft-spring effect and hard-spring effect, respectively. Among the piezoelectric materials, SCNN ceramics possess notable elastic properties. With increasing vibration velocity, their rise in temperature was lower than that of PZT ceramics; in particular, the temperature of SCNN ceramics was lower than that of BNBTM ceramics. The quality factor of BNBTM ceramics gradually decreased and that of SCNN ceramics showed a broad peak. The degradation of the quality factor was thus limited, resulting in a gradual increase in the equivalent mechanical resistance.

Thermal depolarization and electromechanical hardening in Zn2+‐doped Na1/2Bi1/2TiO3‐BaTiO3

“…(1-y)Na 1/2 Bi 1/2 TiO 3 -yBaTiO 3 (NBT100yBT) based material systems have been identified as a potential lead-free replacement in high power ultrasonics (1)(2)(3)(4). Despite early reports on chemical modification of NBT-based materials (5,6) and indications of the potential for applications in high frequency ultrasonics and as surface/bulk acoustic wave substrates (6,7), this material class received less attention due to the relatively poor piezoelectric properties and lower thermal stability in comparison to lead-based materials (8,9).…”

High-power Characteristics of (Bi,Na)TiO3-BaTiO3 Ceramics and Application in Miniature Ultrasonic Motor

“…The maximum rotational speed was determined to be 898 rpm at a preload of 2 N and 922 rpm at a preload of 3 N. Table 2 shows the performance comparison of our proposed ultrasonic motor with existing miniature ultrasonic motors that use the PZT multilayer transducer (15) and crystal-oriented (Sr,Ca) 2 NaNbO 15 transducer. (16) (Sr,Ca) 2 NaNbO 15 is a lead-free piezoelectric material with great high-power characteristics reported by Doshida et al (9,10) Our proposed ultrasonic motor showed the smallest piezoelectric constant (d 33 = 77 pC/N) and a higher rotational speed than the lead-free ultrasonic motor. We have to consider that Doshida et al used 31 mode piezoelectric vibration of stator transducer, but our proposed motor realized high rotational speed owing to the multilayered structure and BNBT's high-power characteristics.…”

“…(Bi,Na)TiO 3 -BaTiO 3 (BNBT) ceramics are one of the lead-free piezoelectric materials with such great high-power characteristics. (9,10) In this research, we evaluated the high-power characteristics of BNBT ceramics quantitatively by evaluating complex higher-order elastic constants. (11) Admittance curves of BNBT and PZT transducers were measured and complex higherorder elastic constants were obtained by curve fitting using a nonlinear piezoelectric vibration model.…”

Colloidal processing using UV curable resin under high magnetic field for textured ceramics

“…The raw powder used in this study was synthesized (Sr,Ca) 2 NaNb 5 O 15 (hereafter referred to as SCNN) powder, which was prepared by the conventional solid-state reaction [32]. This powder was de-agglomerated in an azeotropic mixture solvent consisting of methyl ethyl ketone (MEK) and ethanol (EtOH) (60/40 vol.)…”