Department of Physics, Engineering Physics & Astronomy

Department of Physics, Engineering Physics & Astronomy
Department of Physics, Engineering Physics & Astronomy

Departmental Colloquium - Emerging Electromagnetic Nondestructive Evaluation Technologies for In-Service Inspection

Thomas W. Krause
Department of Physics,Royal Military College of Canada, Kingston, ON, Canada, K7K 7B4

Date: March 11th, 2016
Time: 1:30 p.m.
Location: Theatre A


Nondestructive inspection is used to indirectly evaluate the condition of structural materials without affecting their continued application. Structures are most often periodically inspected to ensure their continued safe operation, particularly in critical safety industries, such as nuclear power plants, aircraft and oil and gas pipelines. Examples of inspection applications include the detection of cracks in multi-layer wing structures of aircraft, cracks and frets in nuclear steam generator (SG) tubes, and measurement of wall loss in steel components including insulated pipe and SG tube support structures.   Challenges for the development of technologies that are applied to in-service inspection include rapid scanning, presence of multi-layer structures, close proximity of dissimilar materials, varying geometry and difficult to access surfaces including those under coatings and insulation.  Electromagnetic inspection technologies have several advantages over other commonly used nondestructive techniques such as ultrasonics, X-ray or liquid dye penetrant.  These advantages include rapid, non-contact inspection for surface and near surface flaws in multilayer components and tubular structures from either the inner diameter or the outer diameter through insulation.  Disadvantages include limited depth of penetration and the requirement for development of advanced signal analysis tools.  This presentation examines several emerging electromagnetic inspection technologies, with a focus on applications to an in-service inspection environment. The targeted methods include: eddy current signal analysis and modeling, pulsed eddy current technique and magnetic Barkhausen noise for ferromagnetic steel component inspection and characterization. Development of technologies for future applications is also presented.