Piezoelectric hysteresis

Figure 13.2 Piezoelectric hysteresis for converse piezoelectric effect in a rhombohedral PZT thin film [3].

Figure 19.10 (a) Piezoelectric hysteresis loops of 256 points (each approx. 30x30nm) obtained by combining phase and amplitude of the induced piezoelectric vibration, (b) Average of the 256 loops [17]. 

By combining the amplitude with the phase information, the piezoelectric hysteresis loops of each point can be calculated and is depicted in 3-dim in Figure 19.10 (a). Figure 19.10 (b) shows the averaged piezoelectric loop of the 256 points. Since the piezoelectric response (amplitude) is in first approximation proportional to the effective dss this averaged loop can be compared with that obtained with a double beam interferometer and therefore used to... 

Domain Growth Kinetics and Piezoelectric Hysteresis for Thin P(VDF-co-TrFE) Films... 

The piezoelectric hysteresis loops have been studied additionally to above dielectric hysteresis. This kind of loop is shown on Fig. 2.17. It has been recorded on PZT nanotube with outer diameter 700 and 90 nm wall thickness with the help of piezoatomic force microscopy (see Refs. [42, 43]). The obtained loop is the direct evidence of ferroelectric properties of the nanotube. Square form of the loop speaks about sharp polarization switching at coercive voltage 2 V. The residual (at zero voltage) piezoelectric coefficient d ff is of the same order as for the thin PZT film. 

Fig. 2.17 Piezoelectric hysteresis loop for PZT nanotube, measured by means of atomic force microscopy [42]...

The peak field-induced response, particularly the mechanical strain Sp, was used to quantify the response of each tested PZT stack. Meanwhile, the piezoelectric hysteresis related to a S-E loop was characterized as... 

After 10 cycles, both the strain and piezoelectric hysteresis of No. 02 were reduced (Fig. 2). A more pronounced reduction was exhibited in the measurement with semi-bipolar loading than with unipolar loading. The strain exhibited a monotonic decrease in the measurement with a bipolar mode along with the accumulation of cycles, whereas that in a unipolar mode showed a restoration at around 10 cycles. The restoration in unipolar loading was also observed in the fatigue of several other PZT stacks The variation of the piezoelectric hysteresis during the cyclic fatigue... 

Curves of normalized quantities versus cycle number describe more clearly the trend associated with a tested stack (Fig. 3). More than 50% decreases in the strain and piezoelectric hysteresis were observed for No. 05, and about 25% decreases were seen for No. 02. For No, 05, the varying degrees of the strain or piezoelectric hysteresis were similar under both loading modes for No. 02, those were somehow different, especially that of the piezoelectric hysteresis. Overall, the degree of reduction in mechanical strain... 

Fig. 2. Variations of peak field-induced strain (a) and piezoelectric hysteresis (b) as a fimction of the number of cycles.

Desfeux, R., Detalle, M., Wang, G.S., and R miens, D. (2008) Local piezoelectric hysteresis loops for the study of electrical properties of 0.7Pb(Mgi/3Nb2/3)O3-0.3PbTiO3 thin films bottom electrode dependence and film thickness effect. Ferroelectrics, 362 (1), 21-29. 

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