摘要:
An oxygen concentration detector 90 includes a one-end closed cylindrical oxygen sensing element 91 having an inside electrode 32, outside electrode 31 provided on the inner side and outer side respectively, an electrode protecting layer 2 made up of ceramics porous member provided further outside the outside electrode, and a trap layer 1 of ceramics porous member having a surface roughness of 20 to 100 µm measured according to a 10 point mean roughness measurement and provided outside the electrode protecting layer 2 is employed. By dipping the to-be-detected gas side surface of an oxygen sensing element into a slurry with coarse heat-resisting metal oxide particles, 2 to 50 µm in average grain size, dispersed, depositing the slurry on the surface of a protective layer of an oxygen sensor element, thereafter drying and baking the deposit, a porous poisonous substance trap layer, 10 to 500 µm thick, is formed. The dipping is performed after a previous degassing and strong stirring of said slurry and the stop of stirring.
摘要:
A multilayered air-fuel ratio sensing element has a zirconic solid electrolytic body (11) and a heat-generating portion (13, 16, 22) including an alumina substrate located adjacent to the zirconic solid electrolytic body (11). The zirconic solid electrolytic body (11) is made of a partially stabilized zirconia containing 5∼7 mol% yttria and having a mixed phase structure including a cubic phase, a monoclinic phase and a tetragonal phase. The zirconic solid electrolytic body (11) has a relative density of 94∼100% with a mean sintered grain size (R ZR ) of 0.5∼3.0 µm. The alumina substrate has a relative density of 95∼100% with a mean sintered grain size (R AL ) of 0.5∼4.0 µm. And, the partially stabilized zirconia has an M/C ratio in a range from 0.05 to 0.25.
摘要:
An oxygen concentration detector 90 includes a one-end closed cylindrical oxygen sensing element 91 having an inside electrode 32, outside electrode 31 provided on the inner side and outer side respectively, an electrode protecting layer 2 made up of ceramics porous member provided further outside the outside electrode, and a trap layer 1 of ceramics porous member having a surface roughness of 20 to 100 µm measured according to a 10 point mean roughness measurement and provided outside the electrode protecting layer 2 is employed. By dipping the to-be-detected gas side surface of an oxygen sensing element into a slurry with coarse heat-resisting metal oxide particles, 2 to 50 µm in average grain size, dispersed, depositing the slurry on the surface of a protective layer of an oxygen sensor element, thereafter drying and baking the deposit, a porous poisonous substance trap layer, 10 to 500 µm thick, is formed. The dipping is performed after a previous degassing and strong stirring of said slurry and the stop of stirring.
摘要:
A multilayered air-fuel ratio sensing element has a zirconic solid electrolytic body (11) and a heat-generating portion (13, 16, 22) including an alumina substrate located adjacent to the zirconic solid electrolytic body (11). The zirconic solid electrolytic body (11) is made of a partially stabilized zirconia containing 5∼7 mol% yttria and having a mixed phase structure including a cubic phase, a monoclinic phase and a tetragonal phase. The zirconic solid electrolytic body (11) has a relative density of 94∼100% with a mean sintered grain size (R ZR ) of 0.5∼3.0 µm. The alumina substrate has a relative density of 95∼100% with a mean sintered grain size (R AL ) of 0.5∼4.0 µm. And, the partially stabilized zirconia has an M/C ratio in a range from 0.05 to 0.25.