Research and development of magnetic non-destructive testing techniques

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In high-impact fields such as the oil and gas and nuclear industries, the consequences of failures can be catastrophic.  My work involves the development of magnetic non-destructive evaluation (NDE) techniques to detect areas of localized high strain which threaten the integrity and safe operation of engineering systems.  Techniques based on magnetism are the best suited to strain measurement, since other methods (e.g. eddy current, ultrasonic) are much less strain sensitive.  However, the correlation between magnetic behaviour and strain is very complex in engineering materials and not well understood.   This Discovery grant funding will further my long term goals of understanding and exploiting the magnetic response of strain in ferromagnetic engineering materials.     The Magnetic Flux Leakage (MFL) and Magnetic Barkhausen Noise (MBN) techniques are well suited to strain measurement. MFL is used to find defects in oil and gas pipelines, but further development is necessary to adapt it for locating high-strain regions such as dents and gouges.  MBN is a leading candidate for finding stressed regions in the steel feeder tubes used in CANDU reactors, but there are many practical obstacles to its use.   The proposed grant will fund three projects: The first examines the relationship between magnetic behaviour and "intergranular" strain (strain in a particular crystallographic direction). The second study aims to characterize and understand the magnetic response of severely plastically deformed steels, enabling us to recognize the magnetic "signature" of dents and gouges.  The third aspect of the Discovery-grant funded work will look at some of the engineering aspects in adapting MBN probes to use in industry.      Finally, mine is the only university-based group in Canada to provide students with training and experience in magnetics engineering.  This training is extremely important in the science-based economic sector, and my graduates have found immediate employment in Canada's high-tech, oil and gas, and nuclear industries.