Electrostrictive Coefficients of Pb(Mg1/3Nb2/3)O3 Ceramics

Abstract

The electrostrictive coefficients Q33 and Q13 of Pb(Mg1/3Nb2/3)O3 ceramics have been precisely determined over a wide temperature range from -110°C to 100°C, using three different methods: strain gauge, piezoelectric resonance and interferometric techniques. A quadratic relation between induced strain and electric polarization holds even in the ferroelectric phase, as well as in the paraelectric phase. The electrostrictive coefficients are nearly temperature-independent with values of Q33=2.3(±0.2)×10-2 m4C-2 and Q13=-0.64(±0.05)×10-2 m4C-2. The field-induced piezoelectric coefficients d33 and d31 were also measured at room temperature as a function of dc bias field. The values of d33/ε3 and d31/ε3 are proportional to the induced electric polarization. The electrostrictive coefficients calculated from the slopes are in good agreement with those obtained by the strain-gauge method.