低压氧化锌压敏陶瓷的显微结构及其电学性能的研究

研究了一价碱金属离子掺杂对低压ＺｎＯ压敏陶瓷电学性能的影响规律,探讨了烧结温度、降温速度对其显微结构和电性能的影响,分析了添加剂驰骋合成对ＺｎＯ压敏陶瓷场强的影响规律。实验发现：一价碱金属离子掺杂能有效地抑制漏流,增加非线性,但同时使压敏场强增加：提高烧结温度能有铲地降低压敏场强,但过高的烧结温度将使漏流增加,非线性系数下降。通常,烧结温度以不超过１２５０℃为宜;添加剂预合成能降低ＺｎＯ压敏陶瓷的     

低压压敏陶瓷烧成过程中的温度因素研究

通过对低压压敏陶瓷烧成过程中的温度进行研究，并对电性能和微观结构进行对比分析，得到了ZnO—PoO系低压压敏陶瓷烧结过程中的最佳烧成温度、升温速率和保温时间，分别为：烧成温度1000％、升温速率3％／min、保温时间2h。并结合微观结构及电性能，测试分析和探讨了其影响机理。     

高梯度大通流氧化锌阀片的研究进展

随着中国电网向特高电压等级发展,特高压电网对高压金属氧化物避雷器(MOA)的国产化提出了更高的要求.总结了国内外在掺杂、粉体制备、烧成工艺方面竞相开展的提高ZnO 阀片电位梯度和通流能力的研究开发工作,并展望了研究前景,指出了突破添加剂粉体筛选、预处理、控制晶粒生长和微观均匀性以及纳米技术与微波烧结相结合是提高ZnO阀片电位梯度和通流容量的主要途径.     

Nb2O5掺杂对TiO2陶瓷性能的影响

在Nb2O5含量x为0.1～1.5%的范围内,研究了Nb2O5掺杂对TiO2压敏陶瓷电性能的影响.发现x＝0.7%的样品显示出最低的压敏电压(Eb=8.57V/mm )以及最高的相对介电常数2.385×104.分析认为Nb2O5掺杂的实质是Nb5 固溶于 TiO2中取代Ti4 使晶粒半导化,但掺杂量受晶格畸变作用有一定限制.     

能量脉冲对ZnO压敏电阻静态老化性能的影响

研究了能量脉冲对高能ＺｎＯ压敏电阻在可控硅整流电压下的静态老化性能的影响以及可控硅整流电压的过电压对压敏电阻的作用。过电压使压敏电阻流过频率为３００Ｈｚ的脉冲电流，从而使晶界势垒高度下降和晶粒导电性增加；经受能量脉冲后的压敏电阻的静态老化电流增长速度远大于未经能量脉冲的压敏电阻的静态老化电流增长速度，即能量脉冲使静态老化性能严重变差。     

受主掺杂对ZnO片式压敏电阻材料性能的影响

研究了一价受主Li^＋对ZnO片式压敏电阻材料的电性能和晶界电参数的影响。材料中添加适量的Li^＋离子,可提高压敏电阻的非线性系数、改进器件的漏电流特性。当Li^＋离子添加量从0增加至300mol／ppm时,晶界势垒高度φB由0.7eV增加为0.87eV,晶粒中载流子浓度ND由2.2×10^23／m^3下降为8.5×10^22／m^3,ZnO的电阻率ρg由1.02Ω·cm增加为1.98Ω·cm。     

Sintering effect on ageing behavior of rare earths （Pr6O11-Er2O3-Y2O3 ）-doped ZnO varistor ceramics

The electrical properties and ageing behavior of the rare earths (Pr6O11-Er2O3-Y2O3)-doped ZnO varistor ceramics were systematically investigated at sintering temperature range of 1335-1350°C. With an increase in the sintering temperature, the sintered density increased from 5.41 to 5.64g/cm3 and the average grain size increased from 5.8 to 7.9μm. The varistor properties and ageing behavior were significantly affected by small sintering temperature range of 1335-1350°C. The breakdown field noticeably decreased from 5767 to 3628V/cm with an increase in the sintering temperature. The varistor ceramics exhibited the highest nonlinear coefficient (43.2) at the sintering temperature of 1340°C. The varistor ceramics sintered at 1350°C exhibited a surprisingly excellent stability by exhibiting 0.3% in the variation rate of the breakdown field and 0.3% in the variation rate of the nonlinear coefficient for ageing stress of 0.95 E1mA/150°C/24 h.     

Mechanical Activation of Spinel and Pyrochlore Phases in ZnO Based Varistors

Mixtures of ZnO, Sb₂O₃ and Bi₂O₃ powders corresponding to the stoichiometric compositions of Zn₇Sb₂O₁₂ (spinel) and Zn₂Bi₃Sb₃O₁₄ (pyrochlore) were milled in a shaker mill (SPEX) up to 180 minutes. The influence of the mechanical activation of the powders, as a result of the milling, was determined by Differential Thermal Analysis, Thermogravimetric Analysis and X-ray Diffraction. Additionally, in order to compare to commercial recipes the mixture ZnO + 2.7 wt% Sb₂O₃ + 4.5 wt% Bi₂O₃ was milled in a shaker mill up to 180 minutes. Varistor devices were fabricated with both milled and unmilled mixtures. The devices were characterized by I-V studies, Scanning Electron Microscopy and X-ray Diffraction. Mechanical activation on the system ZnO-Bi₂O₃-Sb₂O₃ produced a chemical reaction and amorphization in the powder mixture. The weight loss due to volatilization of Bi₂O₃ and Sb₂O₃ that occurrs in both ZnO-Sb₂O₃ and ZnO-Sb₂O₃-Bi₂O₃ systems at temperatures below 1200C is reduced by milling the powder mixtures.     

纳米复合技术改善ZnO压敏电阻微观结构及电性能一致性的研究

采用氨浸法制备ZnO纳米复合压敏瓷料的工艺手段,研制出压敏场强大于330V/m m,漏电流小于1μA,非线性系数大于58的压敏电阻器,电性能的一致性要优于普通压敏电阻器的5～10倍。用扫描电镜和能谱对瓷体显微结构及面扫成分进行了分析,讨论了ZnO压敏电阻材料结构和电性能的关系。研究表明,加入纳米复合粉制备压敏电阻是降低大规模生产中的成本,提高ZnO压敏电阻电性能及其一致性的有效途径。