The cover photo of July 2019 issue is dedicated to the 41st anniversary of the first reported synthetic approach of dendritic hyperbranched structure. The cover photo adopted from the Valer et al., where they reported the preparation of dendritic hyperbranched copolymers based on bis(hydroxyl methyl) propionic acid polyester and studied the architecture - behavior - properties relationship. Dendritic structures are known for their perfect chemical definition, highly dense structure, and a well-defined number of surface functionalities. The soft multifunctional modifications could be compliant to valuable flexibility for embedding different chemical moieties on the surface either within the structure or at the core.
Selecting the correct electromagnetic inspection technology
Thomas W. Krause*, P. Ross Underhill
Department of Physics and Space Science, Royal Military College of Canada, Kingston, ON, K7K7B4, Canada
Adv. Mater. Lett., 2019, 10 (7), pp 441-448
Publication Date (Web): Jan 19, 2019
Copyright © 2019 VBRI Press
Eddy current (EC) technology for inspection of conducting materials is a potential solution when conditions preclude the application of other methods. Such conditions include presence of sound absorbing coatings, unavailability of a couplant, multiple conducting layers with air gaps, limited access or near surface cladding. However, the choice of a particular EC technology may not be clear due to sources of electromagnetic interference, choice of probe design, target configuration or even available equipment. In addition, the choice of EC based technologies is extensive, including conventional EC, low frequency EC, remote field EC and pulsed EC. Each of these technologies has its own challenges and limitations, which need to be considered prior to a commitment to system development. Probe choice becomes a function of the particular technique that has been selected and may include ferrite core sensing coils, GMRs or eddy current coil array. Finally, EC signal analysis methods need to be selected based on effects of potentially multiple varying parameters. This paper examines the potential of electromagnetic inspection technology, discussing its limitations, effects of common essential parameters and analysis methodologies. Examples of recent technology applications are given and the benefits and limitations of various technologies are compared and discussed.
Eddy current testing, pulsed eddy current testing, low frequency eddy current testing, remote field eddy current testing, electromagnetic inspection, non-destructive evaluation.