Jin Min, Xu Jiayue, Shi Minli, Wu Xianjun, Tong Jian
Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, China.
Ultrasonics. 2007 May;46(2):129-32. doi: 10.1016/j.ultras.2007.01.002. Epub 2007 Jan 14.
Novel piezoelectric crystal (1-x)Pb(Zn(1/3)Nb(2/3))O(3)-xPbTiO(3) (PZNT) has attracted much attention due to its high piezoelectric properties and potential applications in medical ultrasonic devices, sonar transducers, solid state actuators. However, the applications of PZNT crystals are limited by the lack of a simple and reproducible growth technique. In this work, large size PZNT crystals were grown by the vertical Bridgman method using 50 mol% PbO as a flux. The growth conditions were optimized as mole ratio of raw materials and flux=1:1, soaking temperature 1150-1200 degrees C, soaking time 10 h, the lowering rate of the crucible 0.5 mm/h and the temperature gradient near solid-liquid interface about 50 degrees C/mm. The maximum size of as-grown PZNT crystal was about 60 mm in length. The crystal was oriented and its piezoelectric constant d(33) and coupling coefficient k(33) were measured over 2000pC/N and 0.92, respectively.
新型压电晶体（1-x）Pb（Zn（1/3）Nb（2/3））O（3）-xPbTiO（3）（PZNT）因其高压电性能以及在医用超声设备、声纳换能器、固态致动器等方面的潜在应用而备受关注。然而，PZNT晶体的应用受到缺乏简单且可重复生长技术的限制。在本工作中，采用50 mol%的PbO作为助熔剂，通过垂直布里奇曼法生长出了大尺寸的PZNT晶体。生长条件优化为原料与助熔剂的摩尔比为1:1、浸泡温度1150 - 1200℃、浸泡时间10 h、坩埚下降速率0.5 mm/h以及固液界面附近的温度梯度约为50℃/mm。生长出的PZNT晶体的最大尺寸约为60 mm长。对该晶体进行了取向，并测量其压电常数d（33）和耦合系数k（33），分别超过2000 pC/N和0.92。
