Microwave and Millimetre Wave Sensors for Crack Detection


Non-destructive detection and evaluation of stress-induced fatigue cracks in metals is an important practical issue in several critical environments including surface transportation (steel bridges, railroad tracks, railroad car wheels, etc.), aerospace transportation (aircraft fuselage, landing gears, etc.) and power plants (steam generator tubings, etc.). Although there are several standard non-destructive evaluation techniques, near-field microwave and millimetre wave techniques have shown tremendous potential for significantly adding to the available non-destructive 'toolbox' for this purpose. This paper serves as a review of recent advances made in this area and the capabilities of these techniques for detecting cracks and evaluating their various dimensional properties including determining a crack tip location accurately. These techniques include using open-ended rectangular probes (in two distinct modes) and open-ended coaxial probes.


Electrical and Computer Engineering

Keywords and Phrases

Aircraft Landing Systems; Aircraft Plants; Crack Detection; Crack Tips; Electric Power Plants; Electromagnetic Waves; Fuselages; Image Sensors; Landing Gear (Aircraft); Microwaves; Millimeter Waves; Power Plants; Railroad Transportation; Railroads; Sensor Networks; Steam Power Plants; Steel Bridges; Aircraft Fuselages; Coaxial Probes; Critical Environments; Dimensional Properties; Evaluating; Fatigue Cracks; Landing Gears; Millimetre Waves; Near-Field; Non-Destructive Evaluations; Open-Ended Probes; Practical Issues; Steam Generator Tubings; Surface Transportations; Wave Sensors; Cracks; Crack

International Standard Serial Number (ISSN)


Document Type

Article - Journal

Document Version


File Type





© 2008 John Wiley & Sons, All rights reserved.

Publication Date

01 Aug 2008