Study on stability and veracity of Pt/Air sensor in liquid lead-bismuth

Measurement and control of oxygen content in liquid lead-bismuth is one of the key technologies in accelerator-driven subcritical system (ADS). It plays a vital role to resist structural material corrosion. Liquid lead-bismuth oxygen measurement and control experimental device was designed and constructed independently to study the key technology. Pt/Air reference electrode oxygen sensors were tested for the stability and veracity in the saturated oxygen concentration with the device. The results showed that in the temperature ranging from 625 ∼ 786 K, it performed good stability after relaxation time less than 750 s for thermal equilibrium relaxation affect by the low heat conduction of YSZ ceramic tube. The voltage signal of Pt/Air sensor was in good agreement with the theoretical value, with absolute deviation less than 10 mV and relative deviation less than 1.5%. Reason for deviation came from thermoelectric voltages and oxide impurities. (authors)