Process for detecting voids in ceramic bodies
AssigneeNGK Insulators, Ltd.
InventorsKazuyoshi Shibata, Toshihiko Suzuki
Life of this patent
Estimating the term…
Abstract
A process for detecting any defect in a ceramic body, including the steps of forming an electrically conductive layer in any such defects including fine voids present in the ceramic body, and then detecting presence or absence of the defect by measuring electrical conductivity between two given points shorted by the electrically conductive layer. The electrically conductive layer may be formed by penetrating an electrically conductive liquid into the defect. Alternatively, the electrically conductive layer may be formed by penetrating a penetrable liquid capable of forming the electrically conductive layer by thermal treatment or chemical treatment and thermally or chemically treating same.
Claims11
A process for detecting voids in a ceramic body, comprising:
- penetrating a penetrable liquid into any void present in the ceramic body, said penetrable liquid being adapted to form carbon upon thermal treatment;
- thermally treating the ceramic body after penetration to carbonize the penetrable liquid thereby forming an electrically conductive layer in any such void present in the ceramic body;
- and
- detecting the presence or absence of the void by measuring electrical conductivity between two points separated from each other and shorted by said electrically conductive layer.
A process for detecting voids in an oxygen sensor, comprising:
- penetrating a penetrable liquid into any void present in the oxygen sensor, said penetrable liquid being adapted to form carbon upon thermal treatment;
- thermally treating the oxygen sensor after penetration to carbonize the penetrable liquid thereby forming an electrically conductive layer in any such void present in the oxygen sensor;
- and
- detecting the presence or absence of the void by measuring electrical conductivity between two points separated from each other and shorted by said electrically conductive layer.
Dependencies are inferred from the claim text.