Method and apparatus for inspecting surface defects
US4914378A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 20, 1988 |
| Grant date | Apr 3, 1990 |
| Priority date | — |
| Expiry date | Jun 20, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/20
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and an apparatus for detecting defects in the surface of a metal material relying upon the potential drop method. Namely, a method of precisely determining the shape of crack from a distribution of potential differences in the vicinity of crack by arranging power supplying electrodes and measuring electrodes on the surface of the metal material in the form of a matrix, and switching the electrodes that supply electric current and the electrodes that measure potential differences to measure distributions of potential differences in many directions, and an apparatus for detecting surface defects relying upon the potential drop method. In the apparatus for detecting surface defects, the arrangement of power supplying electrodes and supply currents are optimized to precisely detect the shape of crack in the surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.