【摘要】 实验研究了驰豫铁电单晶PMN-PT(67/33)分别在等静水压和定向应力的情况下,其介电性质的变化,分析了介电常数和介电损耗的变化趋势.结果表明,介电常数随静水压的增大缓慢增加,压力在10MPa内其相对变化小于2%,介质损耗均小于0.01;而在定向应力均匀增大的情况下,介电常数和介电损耗均出现峰值现象.更多还原

【Abstract】 Single crystal PMN-0.33PT(abbreviated as PMNT)exhibits high piezoelectric coefficient(d_ 33 ～2500pC/N)and electromachanical coupling coefficient (k_ 33 ～94%),it has promising potential of ultrasonic transducer and actuator applications. The single crystals were investigated with focus on the stability of dielectric properties with hydrostatic pressure and directional pressure. It was demonstrated that the permittivity slowly increased with pressure augment, it’s relative varietywas less than 2% within hydrostaticpressure of 10MPa, the dielectric loss was less than 0.01. while applying directional pressure on electrode faces, dielectric constant and dielectric loss of single crystal displayed the peak value.更多还原