We demonstrated high free dielectric permittivity (ε ₃₃ ^T/ε ₀)>8000 and piezoelectric coefficient d ₃₃>1950 pC/N of 72Pb(Mg_1/3Nb_2/3)O₃-28PbTiO₃ (PMN–28PT) single crystals (SCs) obtained by low-voltage AC poling (LV ACP) of 1.5 to 3.5 kV_RMScm⁻¹ at a high temperature (HT) of 80 C in an air atmosphere. The minimum standard deviation (σ) of 170 was similar to conventional DC poling (DCP) and a high average ε ₃₃ ^T/ε ₀ of 8800 was confirmed with a 2.0 kV _RMScm⁻¹ of ACP for five samples. The ACP voltages were less than 50% compared with previous studies of 2.9 to 8.5 kV _RMScm⁻¹. We assume ACP at 80 C with a frequency of 0.1Hz decreased coercive field E _C the most which led to easy poling reversal. The LVHT air ACP process is very effective in obtaining enhanced dielectric and piezoelectric properties for PMN–PT SC transducers for medical echo ultrasound equipment application with less risk of breakdown and organic solvent-free for poling.

我们证明了 72Pb(Mg _1/3 Nb _2/3 )O ₃ -28PbTiO ₃ (PMN–28PT) 单晶的高自由介电常数 ( ε ₃₃ ^T / ε ₀ )> 8000 和压电系数d ₃₃ >1950 pC/N (SC) 通过 1.5 至 3.5 kV _RMS cm ^-1的低压交流极化 (LV ACP)在 80 C 的高温 (HT) 空气气氛中获得。170的最小标准偏差 ( σ ) 与传统直流极化 (DCP) 相似，并且8800的高平均值ε ₃₃ ^T / ε ₀被证实为 2.0 k 五个样本的 ACP 的V _RMS cm ^-1。与之前研究的 2.9 至 8.5 k V _RMS cm ^-1相比，ACP 电压小于 50% 。我们假设 ACP 在 80°C 下以 0.1Hz 的频率降低矫顽场E _C最大，这导致容易的极化反转。LVHT 空气 ACP 工艺非常有效地获得增强的 PMN-PT SC 换能器的介电和压电性能，用于医疗超声超声设备应用，具有较低的击穿风险和无有机溶剂用于极化。