4.3. X-ray backscatter imaging of complex structured aluminium
components
Fig. 15(a) shows the experimental setup used for the back-
scatter inspection of heterogeneous aluminium specimen. In order
to achieve large penetration depths and to image significant
thickness variations (in between 5 mm and 65 mm) in the alumi-
nium component, we used a high power X-ray source (GE ISOVOLT
Titan E) with a maximum voltage of 420 kV and tube current of
10 mA. A slit width of 0.8 mm was used for allowing scattered
radiation from the whole object through the X-ray backscatter
camera. In view of real time backscatter imaging applications, we
selected an exposure time of 3 min.
The measured X-ray backscatter image of the inhomogeneous
aluminium component is shown in Fig. 15(b). A good contrast
among different thickness regions of the aluminium component
can be seen in the image. The side drilled holes of 5 mm diameter
along the corners of the test object are obvious in Fig. 15(b). Fig. 16
shows the measured backscattered intensity profile along the line