Grant: Discovery Grants Program - Individual

The goal of this scientific investigation is to develop portable surface magnetic Barkhausen noise (MBN) capability for non-destructive characterization of ferromagnetic steel properties. The goal includes combined measurement of residual stress, degree of plastic deformation, grain size, carbon content, crystallographic texture, magnetic anisotropy and, in the case of electrical steels, core loss. Motivation for this work is the requirement for rapid identification of steel type and evaluation of stress state within structures such as submarine and ship hulls, oil and gas pipelines, motor or transformer laminates, landing gear in aircraft and cases where structures may have undergone localized damage and/or repair. Development of tools, analysis methods and modeling, along with identification of factors that affect the measurement outcome will facilitate application of MBN analysis and advance its potential as a diagnostic tool for identification and characterization of steel materials. The scope of work will include characterization of a wide range of steel materials, in order to develop models of MBN generation that will allow the extraction of key material parameters for non-destructive characterization of materials. The five year project will examine Barkhausen noise emissions from a number of steel types with the goal of developing general models describing micro-magnetic Barkhausen emissions in order to enhance MBN inspection capabilities for future applications. The specific ferromagnetic steel properties to be evaluated will include characterization of magnetic properties and optimization of core loss and permeability in non-oriented electrical steels (NOES), the detection and measurement of residual elastic and/or plastic stress in structural steels, including naval vessels, with a focus on monitoring of fatigue and carbide precipitate migration, as may occur during tempering embrittlement in HY80, used for submarines, and identification/assessment of specific steel grades, such as would be useful in the oil and gas industry, where installed pipelines may be made of unknown steel material. Barkhausen noise will be examined for specific NOES steels obtained under controlled manufacturing processes, as part of a collaboration with CanmetMATERIALS, Natural Resources Canada (see attached letter indicating in-kind support of $150,000-$250,000 over 5 years). Determination of naval steel condition including presence of elastic residual stress, plastic deformation and potential for detection and characterization of tempering embrittlement will be performed in collaboration with Defence Research Development Canada (DRDC), Atlantic Research Centre (see attached letter of support). Identification of signal parameters that could be used to identify steels will be performed in collaboration with Lynann Clapham at Queen's University and CanmetMATERIALS.