| This thesis is mainly base on the study of different concentration oxygen sensor for automobile and also gives attention to that of limiting current oxygen sensor. According to the produce flow of oxygen sensor, the powder preparation technology, sintering techniques, character of electrode, technology remark of finished product, measuring method and measuring equipments for solid electrolyte yttrium stability ZrO2, which is the key part of different concentration oxygen sensor for automobile, ware careful studied.At first, the preparation technology and character of nano-powder of 9mol%Y2O3 doping ZrO2 ware mainly researched in the second chapter. In this chapter, the preparation technology of the co precipitation process with ammonia as precipitator, co precipitation process with oxalate as precipitator, and modified Sol-Gel process, respectively, ware introduced. The affection of preparing, dehydrating, drying, rubbing to the production of agglomeration ware studied. The characteristics of the powders were analyzed by TG—DTA,TEM, XRD,and laser granulometer. The results showed that rigid agglomeration can be decreased effectively by adding surfactant, ultrasonic washing with anhydrous alcohol distillation process. YSZ nano-powders with homogenous grain distribution and average grain size of 14 nm were prepared by modified Sol-Gel process.The sintering technology and characters of the ceramic for nano-powder of Y2O3 doping ZrO2 ware mainly researched in the third chapter. in this chapter the sintering technology by convention sintering(CS) , spark plasma sintering(SPS)and microwave sintering(MS)methods were studied,the microstructure, phase, mechanics character and electro character of the sintered samples ware analyzed by SEM,XRD,complex AC Impedance and Anti-cure intension measuring method . The results showed that convention sintering system is simple and useful sintering method and suitable to batch manufacture. The sintering temperatures of CS have obvious affection to the relative density; anti-cure intension and crystal appearance .the sample, which have higher relative density and anti-cure intension, can be gotten by forming with isopressure. Owing to the "clipping" affection, the appearances of microstructure of sample by microwave sintering are very strong and show "bar" or "slice" form, in addition, the pole area of microstructure is bigger. The phase of sample by microwave sintering is complex. By the SPS, the samples which the relative density is 99%,and the grain size is as small as 0.8μm can be gotten in lower sintering temperature(1350℃) and shorter sintering time (less more than 30 min) ,the conductance of grain and grain boundary of SPS sample are different to the CS sample, The context of the four chapters is about on the electrode character of oxygen sensor. In this chapter, a new model of the electrode and electrolyte interface (Pt /YSZ) ware published, the length of triple phase boundary of electrode at different electrode sintering temperature and different aging time were calculated by this model. By means of equipment of SEM and complex AC impedance, as well as I-V polarization curve, the mechanism of electrochemistry to oxygen sensor ware researched. The results showed that the electrics characteristic of oxygen Sensors and electrode appearance of the Pt/YSZ(yttria stabilized zirconia) electrode structure at different aging time show notable change, In addition, notable change of the electrics characteristic of oxygen Sensors and electrode appearance at different electrode sintering temperature can be also gotten. Same sample at different measuring temperature shows two types of the mechanism of electrochemistry .the activation energy of electrode of samples show almost same value, it make sure that the activation energy of electrode of samples is only depended on material of Pt and don't relative to the produce technology.The response time is main technology parameter of oxygen sensor for automobile. On the basis of the actual application for ox...
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