ZnO压敏电阻器制备过程对电性能的影响

发布时间：2018-05-16 06:21

  本文选题：ZnO压敏电阻 + 电性能　； 参考：《华南理工大学》2014年硕士论文

【摘要】：ZnO压敏电阻器由于其优良的非线性特性和强耐浪涌能力，被用来对各种电力系统和电子线路进行过电压保护。如今，随着电力系统及电子线路的快速发展，对ZnO压敏电阻材料的安全可靠性以及体积的小型化等方面提出了更高的要求，因此制备出高性能的ZnO压敏电阻材料是目前的主要研究热点。而ZnO压敏电阻材料的性能在很大程度上由原料的性质、配方成份和制备工艺决定，为了制备出综合性能优良的ZnO压敏电阻材料，本文研究了ZnO压敏电阻制备过程对其电性能的影响，并对制备过程进行优化。主要研究内容和研究结果如下： 1、研究了聚丙烯酸铵分散剂量和球磨时间对ZnO压敏电阻材料电性能的影响。研究表明，适量的聚丙烯酸铵分散剂配合适当的球磨时间可有效提高ZnO粉体与添加剂的球磨混合效率，改善ZnO压敏电阻材料的小电流特性和大电流特性。 2、研究了ZnO压敏电阻的排胶热过程及排胶工艺对ZnO压敏电阻电性能的影响。研究表明，ZnO压敏电阻用粉料中残留自由水的挥发温度区间为室温至150℃，聚乙烯醇粘合剂的分解、挥发温度区间主要为200~350℃，Sb2O3发生氧化反应的温度区间为500~600℃，且Sb2O3的氧化会引起较大的体积收缩。合理的排胶过程能减少材料耗尽层中氧空位缺陷的存在，降低施主浓度，使得晶界势垒高度增加，从而提高材料的非线性系数，，同时，排胶能提高材料的致密性和结构均匀性，减小材料的漏电流，提高材料的耐脉冲电流特性。 3、研究了不同压敏电压梯度ZnO压敏电阻材料的烧结热过程及烧结工艺对ZnO压敏电阻电性能的影响。研究表明，压敏陶瓷材料因配方成分不同烧结热过程差异较大，材料的液相形成温度及致密度随Sb2O3含量的减少及TiO2含量的增多而降低，且烧结温度超过1150℃时，不同组成的ZnO压敏陶瓷材料的Bi2O3相都会加剧挥发。实验还发现，烧结工艺对ZnO压敏电阻材料的电性能影响很大，压敏电压梯度会随着烧结温度升高或保温时间的延长而逐渐降低，但从其他特性测试结果发现，对特定配方材料可试验得出最佳烧结条件，在此烧结条件下可获得较佳电性能，烧结条件不合适会使漏电流增大，非线性特性及耐脉冲电流特性变差。
[Abstract]:Due to its excellent nonlinear characteristics and strong surge resistance, ZnO varistor is used to protect all kinds of power systems and electronic circuits. Now, with the rapid development of power systems and electronic circuits, the safety and reliability of ZnO varistor materials and the miniaturization of volume are higher requirements. The preparation of high performance ZnO varistor material is the main hot spot at present, and the performance of ZnO varistor material is largely determined by the properties of raw materials, composition and preparation process. In order to prepare the ZnO varistor material with excellent comprehensive properties, this paper studied the electrical properties of the ZnO varistor preparation process. The main research contents and results are as follows:
1, the influence of the dispersing dose of ammonium polyacrylate and the ball milling time on the electrical properties of the ZnO varistor is studied. The study shows that a proper amount of ammonium polyacrylate dispersing agent with the appropriate ball milling time can effectively improve the mixing efficiency of the ball milling of the ZnO powder and the additive, and improve the small current characteristic and the large current characteristic of the ZnO varistor material.
2, the influence of the heat process of ZnO varistor and the process of sizing on the electrical properties of ZnO varistor is studied. The study shows that the evaporation temperature range of the residual free water in the ZnO varistor is from room temperature to 150 C, the decomposition of the polyvinyl alcohol adhesive, the temperature range of the volatilization temperature is mainly at 200~350 C, and the temperature range of the oxidation reaction of Sb2O3 occurs. At 500~600 C, the oxidation of Sb2O3 causes large volume contraction. The rational process of sizing can reduce the existence of oxygen vacancy in the material depletion, reduce the concentration of the donor, increase the height of the grain boundary barrier, and increase the nonlinear coefficient of the material, at the same time, the compactness and structure uniformity of the material can be raised and the material leakage can be reduced. Current, improve the pulse current resistance of the material.
3, the influence of the sintering heat process and the sintering process on the electrical properties of ZnO varistor with different voltage sensitive voltage gradient ZnO varistor materials is studied. The study shows that the different sintering heat processes of the varistor ceramic materials are different, the liquid phase forming temperature and density of the material are reduced with the decrease of Sb2O3 content and the increase of the TiO2 content. When the sintering temperature is more than 1150 C, the Bi2O3 phase of the ZnO varistor ceramics with different composition will aggravate the volatilization. It is also found that the sintering process has a great influence on the electrical properties of the ZnO varistor material, and the voltage gradient will gradually decrease with the increase of the sintering temperature or the prolongation of the heat preservation time, but it is found from the test results of other characteristics. The optimum sintering conditions can be obtained for the specific formula materials. Under the sintering conditions, the better electrical properties can be obtained. The leakage current will be increased and the nonlinear characteristics and pulse current characteristics are worse.

【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM54

【参考文献】

相关博士学位论文 前1条

1 卢振亚;氧化物压敏陶瓷晶界特性与宏观电性能的关系[D];华南理工大学;2012年

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