四方相铌镁酸铅-钛酸铅(PMN-PT)铁电单晶的弹性、介电、压电和机电性能

Elastic, Dielectric, Piezoelectric and Electromechanical Properties of Tetragonal Pb(Mg_1/3Nb_2/3)O_3-PbTiO_3 (PMN-PT)

研究了四方相弛豫铁电单晶Pb(Mg1/3Nb2/3)O3-38％PbTiO3(PMNT62/38)的介温特性,并利用HP4192A阻抗分析仪测量了PMNT62/38单晶完整的一套弹性、介电、压电和机电耦合系数,为理论研究和器件设计提供了参考,其居里点Tc～174℃;压电应变常量d33～300pC/N;介电常数C33～734,ε11～4301;机电耦合因数k33～84.6％,kt～60.8％,k31～44.5％,k15～45.9％.

Relaxor ferroelectric single crystal Pb(Mg1/3Nb2/3)O-3-38%PbTiO3 (PMNT62/38) was grown directly from melt by a modified Bridgman technique. The XRD analysis confirms that PMNT62/38 single crystal has a tetragonal structure at room temperature. The epsilon(r) - T peak at T-c and little dispersion over measured temperature range indicate that the PMNT62/38 single crystal is a normal ferroelectric. The full set of electromechanical properties was determined by using an impedance resonance technique, the Curie temperature being about 174degreesC, piezoelectric constant d(33) similar to300pC/N, and permittivity epsilon(33) similar to734 and epsilon(11) similar to4301. Electric-mechanical coupling coefficients measured axe k(33) 84.6%, k(t) 60.8%, k(31) 44.5% and k(15) 45.9%.