【作者】 吴帮军；

【导师】 曾亦可；

【作者基本信息】 华中科技大学 ， 材料物理与化学， 2007， 硕士

【摘要】 随着汽车技术的进步和传感器制造工艺技术的提高,汽车用氧传感器不断的完善发展,其发展前景十分广阔。为克服传统电流型氧传感器的缺点,优化传感器的测试性能,本文研究了用固态电子-离子混合导体作为致密扩散障碍层的极限电流型氧传感器的材料制备。这种氧传感器有更好的氧敏特性,拓宽了传感器的氧测量范围,具有结构简单、响应快、工作可靠、成本低廉等优点,是一种很有前景的极限电流型氧传感器。本文研究了一种新型的注模成型工艺:将钇稳定的氧化锆粉体按一定比例与有机单体、交联剂、分散剂和增塑剂的水溶液混合,得到高固相含量、低粘度的浆料,滴入少许引发剂和催化剂后注模成型。另外制备了新型极限氧传感器的各部分材料,并且进行了材料的改性,对结果进行了分析。电解质材料:采用新型的注凝成型工艺,制备出8%摩尔含量的钇掺杂氧化锆基陶瓷材料,1400℃温度下烧结的YSZ陶瓷已变为单一的立方萤石结构,经1500℃烧结后相对密度可达95.1%,并用此方法可将烧结温度降低100～200℃。在掺入Al2O3后样品的收缩率降低,体密度变大,有更好的烧结性能。扩散层材料:确定了本实验La0.8Sr0.2MnO3样品的烧结温度为1000℃,此时生成La0.8Sr0.2MnO3单一晶相,合成反应基本完成;在1200℃烧结温度下相对密度可以达到97%。在掺Sr实验中随着Sr含量增加,合成La1-xSrxMnO3相对密度降低,烧结性能下降。导电陶瓷材料:掺杂Al2O3的ZnO陶瓷样品随着掺杂量的增加,电阻率略有降低,在Al2O3质量分数为0.5%时达到最小值,并且电阻率随着烧结温度的升高下降很快。而掺杂Y2O3的ZnO导电陶瓷烧结温度为1000℃时,电阻率最大,达到220Ω·cm;电阻率也随着烧结温度的升高而下降,在整个1000℃～1200℃范围内ZnO导电陶瓷电阻率下降幅度达到90%以上。更多还原

【Abstract】 With the development of the technology for automobile and manufacture craft of sensors, automobile oxygen sensors are consummating constantly with a wide developing foreground. To overcome the disadvantage of the traditional current type oxygen sensor and optimize the testing performances of sensor, using solid state electronic-ion mixed conductor as the material of the preparation of limiting current oxygen sensor with a dense diffusion barrier is studied in this article. This kind of oxygen sensor has a better oxygen sensitive characteristic then broadened a sensor measures range. It has many merits such as inexpensive, simple structure, respond quickly and work reliable. So it is the one kind of the limiting current oxygen sensor which has a good prospect.In this thesis, a new gel-casting method has been studied: mix the Y2O3 stabilized ZrO2 powder body with organic monomer, coupler, dispersant and the plasticizing agent according to a certain proportion. Then pour the slurry into a model after drop little initiator and accelerating agent in it. Then it has prepared the materials of each part in the oxygen sensor, carried on the material modification and analyzed the results.Electrolyte material: prepared the Y2O3 stabilized ZrO2 ceramics by a new gel-casting method. YSZ sintered at 1400℃has became the cubic fluorite structure, and sintered at 1500℃whose relative density can reach 95.1%, using gel-casting method can reduce the sinter temperature by 100～200℃. The samples which mixed with Al2O3 have lower rate of contraction, higher volume density, and good sintering character.Dense diffusion barrier material: the best sintering temperature of La0.8Sr0.2MnO3 material is determined 1000℃, synthetic reaction can finish at this temperature. The samples sintered at 1200℃whose relative density can reach 97%. As increasing of strontium in La1-xSrxMnO3, the volume density of the samples decrease and the sintering character descend.Conductive ceramics material: the electrical resistivity of ZnO ceramic will decrease slowly when increasing of the Al2O3, and the electrical resistivity reaches the least when the quality percent of Al2O3 is 0.5%; and the electrical resistivity descend quickly when the sintering temperature raise up. The electrical resistivity of ZnO conductive ceramic mixed with Y2O3 sintered at 1000℃is the biggest which reaches 220Ω·cm . And the electrical resistivity descend when the sintering temperature raise up. When the sintering temperature between 1000℃and 1200℃, the electrical resistivities of the ZnO samples fall over 90%.更多还原