A potential NDT method for rapid quality control of thermal sprayed coatings

An overview on potential non-destructive testing (NDT) methods for the inspection of thermally sprayed coatings in production lines is given The suitability of several NDT techniques has been investigated with view on their sensitivity for the detection of defect sizes possibly being critical for Thermal Spray coatings. Eventually, a method is presented that shows qualification for detection of subsurface flaws in coatings such as delaminations and cracks and offers flaw distinction try image analysis procedures. A storage and archiving of test results is possible thus completing full quality control and meeting possible warranty claims. The major advantage of the NDT process is its very high detection speed which guarantees high productivity even for high volume production systems. Thus a full-area detection of large coated components becomes possible. The process is not restricted to plain components, but is usable for the detection of internally coated cylinders as well.