Application of chromium sensor to measurement of chromium activity in carbon saturated iron melt

The Cr sensor was composed of ZrO2(MgO) solid electrolyte, CaSi03+Cr2O3 auxiliary electrode, Cr+Cr2O3 reference electrode and Mo wire, Mo+ZrO2 stick as lead wire. It can be expressed as: Mo| Cr, Cr2O3| ZrO2(MgO)| CaSiO3, Cr2O3|[Cr]Fe|Mo-ZrO2. The activity of Cr in C-saturated iron melt at 1753 K with different Cr content was determined. About 2-3 s the steady EMF was obtained and its error is within �� 1-2 mV. The relation between activity and content of Cr shows regularity.