- since 1996 -
|NDT.net Issue - 2018-03 - NEWS ||NDT.net Issue: 2018-03|
Publication: e-Journal of Nondestructive Testing (NDT) ISSN 1435-4934 (NDT.net Journal)
Microwave System for the production-oriented Non-Destructive Testing of Leaf Springs made from glass fiber reinforced PlasticFI Test- und Messtechnik GmbH47, Magdeburg, Germany
The company IFC Composite GmbH fabricates more than 1000 glass fiber reinforced leaf springs per day for the minivans Mercedes Sprinter and Volkswagen Crafter. Besides of destructive testing there is a need for non-destructive testing for production surveillance. The approximate size of the leaf springs is 1400 mm x 70mm x 30 mm. Unidirectional glasfiber prepregs are used. The complete volume of the leaf spring is to be tested for inhomogeneities. Here the prototype of a test system for this purpose is described, see figure 1.
Figure 1: Photograph of the Microwave-Based NDT System for GFRP Leaf Springs.
Figure 2: Microwave Scans of Leaf Springs with Artificial Defects.
a) Tranvsers Bore Holes b) Grooves. c) Metal Filament. d) Plastic Foil
Figure 2a shows the C-scan of a leaf spring with transversal bore holes on half height, i.e. 15 mm from lower side and top side. They are recognizable down to diameters of 1 mm.
Figure 2b shows indications of grooves which extend over the whole width of the leaf spring. They are recognizable down to 0.5 mm depth. Figure 2c shows the C-scan of a leaf spring with an oblique metal filament of 0.25 mm diameter at the bottom, i.e. at the receiver side of the microwave modul.
Figure 2d shows the indication of a plastic foil of 0.6 mm thickness. All these artificial defects are clearly recognizable.
This application note shows an example for the use of microwave-based non-destructive testing in a production line. We would like to answer your questions regarding avaible microwave-based measurement and test equipment which can also be made customer-specific and application-specific as well as regarding further use of microwave-based non-destructive testing.