Zirconia Sensors Based on Shaped Eutectic Composites

4 Zirconia Sensors Based on Shaped Eutectic Composites 

FIGURE 4.12 Different design of Al203-Zr02-Y203-shaped eutectic composites. 

The oxygen-sensing properties of sensors based on the AljOj-ZrOj-YjOj eutectic composites and polycrystalline zirconia sensors with the same Y2O3 concentration in the electrolyte were also investigated [53]. All tests were carried out using nitrogen as a carrier gas. In all measurements, the airflow rate was -100 cmVmin. The oxygensensing properties of sensors based on the polycrystalline AljOj-ZrOj-YjOj solid electrolyte were shown for comparison. 

It has been established that the structure of the shaped Al203-Zr02(Y203) eutectic composite, as well as the structure of composites obtained by other methods of directional solidification in this system, consists of two phases the matrix, which is alumina, and stabilized zirconia [47]. In this Al203-Zr02 systan, alumina is the 

Sensing properties of the sensors based on Al203-Zr02-Y203 eutectic composites were investigated in the temperature range of 450-600°C to find the lowest possible temperature at which the output emf of a sensor follows the Nemst equation. Dry 

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