OXYGEN SENSOR OF ZIRCONIA SOLID ELECTROLYTE

摘要

PURPOSE:To improve the wettability of a titled element and to expedite the heat transmission and also, to improve a response velocity, by covering the outer circumference part of a zirconia element by a mixture of metallic oxide powder, an organic binder and metallic fluoride powder or oxide glass powder. CONSTITUTION:3-25pts.wt. organic binder (e.g.; acrylic resin) and optionally 1-10pts.wt. flux composed of metallic fluoride (e.g. CaF2) or oxide glass powder, are mixed with 100pts.wt. metallic oxide powder (e.g. Al2O3) and a solvent is added and then, covering material is obtained by mixing said mixture in a ball mill. Next, after forming a covering film by applying said covering material on the outer circumference of a baggy tubular zirconia element 1, a standard substance 3 (e.g. Cr+Cr2O3) and an electrode rod 4' are put in the baggy tube of the element 1 and a standard oxygen electrode is obtained. The oxygen electrode and the rod 4 are inserted into molten steel and the quantity of oxygen is measured by generating an electromotive force E by oxygen dissolved in the steel.