Solid electrolyte cell for measuring oxygen activity in steel melt - uses oxidic chromium-aluminium cermet as standard solid

摘要

Solid electrolyte cell is used for correction-free measurement of low oxygen activities in steel melts, in which the cell is immersed, by comparison with a standard solid of known oxygen activity surrounded by a solid mixed oxide electrolyte, which conducts oxygen ions but has negligible electronic conductivity at relatively high temps. The novel feature is that the standard solid consists of oxidic mixed crystals, one oxide component (I) of which is an ordinary material for the prodn. of standard substances, whilst the other oxide component (II) has a lower O2 partial pressure, and the mixed crystals of the metal components. The standard solid has an O2 partial pressure in the 10-15 to 10-12 range, as required for the determn. of oxygen activities under 50 ppm in the melt.