两步烧结法对钛酸锶钡陶瓷调谐及击穿性能的影响

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关键词：钛酸锶钡陶瓷；两步烧结法；优值因子；击穿场强；温度稳定性中图分类号：TB34文献标志码：ADOI：10.7652/xjtuxb202510017 文章编号：0253-987X（2025）10-0180-09

Effect of Two-Step Sintering Method on Tunable and Breakdown Properties of Barium Strontium Titanate Ceramics

RAN Dongsheng，LIU Wenfeng，ZHAO Yi，LIANG Yan，LI Shengtao （State Key Laboratoryof Electrical Insulationand Power Equipment，Xi'an Jiaotong University，Xi'an 71049，China）

Abstract： To meet the urgent demand of next-generation electronic tuning devices for high dielectric tunability，superior temperature stability，and strong breakdown performance，barium strontium titanate（BST） is selected as the matrix and co-doped with La and Mn to form （Ba0.675Sr0.325）1-x LaxTi1-xMnxO3 ， where the La and Mn contents are 0.25% ， 0.5% ， 0.75% ，and 1.0% ，aiming to achieve both high dielectric tunability and low dielectric loss.By employing the two-step sintering method and optimizing sintering parameters， ceramic samples with more uniform grain size distribution and denser microstructure are obtained. Experimental results show that compared with the conventional solid-phase sintering method，BST ceramics prepared via the two-step sintering method exhibit smaller and more uniform grain sizes as well as higher density. In terms of dielectric tuning performance，when the La and Mn contents are both 0.5% ，the BST ceramics prepared by the two-step sintering method demonstrate a dielectric tunability of 72.7% ，a dielectric loss of O.Ool，and a calculated figure of merit （FOM） reaching a maximum of 661， nearly 40% higher than the 473 achieved by the solid-phase sintering method. The relative standard deviation of dielectric tunability in the temperature range of -10°C to 60°C is 0.29， approximately 20% lower than that of the solid-phase sintering method. Additionally，the breakdown field strength increases from 118.06kV/cm to 140.19kV/cm ，an improvement of （20 18.7% . The experimental results indicate that the two-step sintering method synergistically enhances both the FOM and breakdown field strength of BST ceramics，meeting the new requirements of temperature stability for next-generation electronic tuning devices and further advancing the potential of BST materials in the electronic tuning device field.

Keywords： barium strontium titanate ceramics; two-step sintering method； figure of merit; breakdown strength；temperature stability

频率振荡器、移相器和变容二极管等电子调谐器件广泛应用于现代移动通信技术，通常要求所用材料的介电常数随外加电场呈显著非线性变化，同时具有低介电损耗[1-3]。（剩余13677字）