Abstract
In recent years magnetic imaging technologies has become a great concern in non-destructive testing (NDT). Due to the advent of highly sensitive magnetic field sensors based on the GMR-effect (Giant Magneto Resistance) the flux leakage (which depends on magnetic inhomogeneities inside the inspected material) can be measured precisely. During the work on this thesis a testing device was developed which is able to detect magnetic flux density variations from mT (millitesla) down to only some nT (nanotesla). Thus defects, corrosion, non-metallic inclusions, surface defects, cracks, specimen thickness variations and even residual stresses can be detected.
The magnetic flux leakage (MFL) method was already applied - of course in a highly simplified way - in the 19th century for detecting flaws in gun barrels and railway tracks. An electro magnet magnetizes the ferromagnetic specimen and the specimen's surface is scanned with the developed testing device.
Keywords: Magnetic Flux Leakage (MFL), Giant Magneto Resistance (GMR), Non-Destructive Testing (NDT).
The circulation of the project work is restricted from January 28, 2013, for a period of 5 years.
| Translated title of the contribution | Development of a measurement system for detecting subcutaneous inclusions in steel sheet |
|---|---|
| Original language | German (Austria) |
| Publication status | Published - Feb 2013 |
Fields of science
- 102003 Image processing
- 202012 Electrical measurement technology
- 202039 Theoretical electrical engineering
- 202037 Signal processing
- 203016 Measurement engineering
- 205016 Materials testing
JKU Focus areas
- Mechatronics and Information Processing