Premium
New reference materials for electrochemical on‐line sensors to measure steel bath composition
Author(s) -
Dimitrov Stefan,
Ranganathan Srinivasan,
Weyl Axel,
Janke Dieter
Publication year - 1993
Publication title -
steel research
Language(s) - English
Resource type - Journals
eISSN - 1869-344X
pISSN - 0177-4832
DOI - 10.1002/srin.199300984
Subject(s) - oxygen sensor , electrolyte , oxygen , electrochemistry , ionic bonding , metallurgy , polarization (electrochemistry) , materials science , flux (metallurgy) , analytical chemistry (journal) , chemistry , thermodynamics , electrode , ion , physics , organic chemistry , chromatography
Further efforts have to be made to develop reliable sensors for on‐line measurements in steel melts. Accurate performance of conventional sensors with a Cr‐Cr 2 O 3 reference over extended periods is disturbed by polarization effects mainly at the solid electrolyte/oxygen reference interface. A promising way to minimize or eliminate this problem is to reduce the flux of ionic oxygen across the solid electrolyte by applying oxygen references featuring oxygen potentials close to the actual oxygen potential of the steel melt. In search of oxygen references with 's lower than that of Cr‐Cr 2 O 3 mixtures, EMF measurements were made to determine the equilibrium oxygen pressures of the systems Cr‐CaO‐CaCr 2 O 4 , Cr‐MgO‐MgCr 2 O 4 , Cr‐Y 2 O 3 ‐Y 2 Cr 2 O 6 , and Nb‐NbO. It is shown that the use of these reference materials enables correct on‐line measurements in fully‐killed steel baths over periods of 4 hours at least.