System and method for non-destructive evaluation of surface characteristics of a magnetic material
US5313405A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 4, 1991 |
| Grant date | May 17, 1994 |
| Priority date | — |
| Expiry date | Sep 4, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/725
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A system and a related method for non-destructive evaluation of the surface characteristics of a magnetic material. The sample is excited by an alternating magnetic field. The field frequency, amplitude and offset are controlled according to a predetermined protocol. The Barkhausen response of the sample is detected for the various fields and offsets and is analyzed. The system produces information relating to the frequency content, the amplitude content, the average or RMS energy content, as well as count rate information, for each of the Barkhausen responses at each of the excitation levels applied during the protocol. That information provides a contiguous body of data, heretofore unavailable, which can be analyzed to deduce information about the surface characteristics of the material at various depths below the surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.