Laser glazing holds great potential for the production of new and improved materials, but there is a need to identify and control the thickness of the glazed layer and to monitor porosity and other defects in the surface layer and adjacent substrate by using nondestructive evaluation techniques. Eddy current methods rely on the interaction of electromagnetic fields with the metallic part under test, which effectively transfers the impedance of the test specimen to the excitation coil so that changes in the test specimen which affect the transferred impedance may be detected by the test coil. This paper addresses the experimental parameters of laser glazing of metallic surfaces, eddy current probe suitability for reliable measurement of thin layers, ranges of operating conditions, sensitivity, speed of response and feasibility of eddy current nondestructive sensors for use in process control.
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