摘要 |
<p>A method for the detection of delaminated areas in coated materials or layered composites, which allows free-air operation and can be used to scan portions of bulky materials on the spot. This method which makes it possible to detect very small delaminated areas in a very short time (less than 1 millisecond), with a very high sensitivity and without creation of excessive thermal stress in the inspected material, basically comprises the steps of: focusing pulsed, thermal radiations onto the structure to be inspected to produce a vertical displacement of its coating by thermal expansion if a delaminated area is present at the coating-to-substrate interface, and detecting and measuring this vertical displacement if any, by interferometry, preferably laser-beam interferometry. An apparatus for carrying out this method is also disclosed.</p> |