Non-destructive testing

X-ray methods

© Fraunhofer IKTS
Examination of an electronic assembly using high-resolution x-ray laminography.
© Fraunhofer IKTS
X-ray CT of a single-handed pocket watch, manufactured around 1600 (exhibit item on display at Staatliche Kunstsammlungen Dresden).

Micro-computed tomography

Industrial micro-computed tomography (micro-CT) is an established method of analysis for technical and scientific applications and is increasingly established in the investigation of artistic and cultural goods. It is ideal for visualizing air inclusions, cracks, and other material inhomogeneities in objects of any shape. Micro-CT enables non-destructive three-dimensional examination of objects with a high spatial resolution.

Fraunhofer IKTS has a micro-CT system that can be adapted to customer requirements. This makes it possible to investigate objects ranging from miniature electronic components to large art objects and fossils.

Technical details

  • 225 kV microfocus x-ray tube
  • 2048 x 2048 pixel area detector
  • Spatial resolution: max. 1 μm
  • Specimen size: max. 60 cm (greatest extension)
  • Specimen weight: max. 6 kg

Application fields

  • Materials and product development for electronics industry and medical technology
  • Examination of mass-produced parts
  • Examination of archaeological finds and art objects

High-resolution CT laminography


High-resolution computed laminography (HRCL) is a new x-ray tomography method that was developed at Fraunhofer IKTS. With it, small regions of especially large-area and planar circuit substrates can be investigated non-destructively at a high resolution. With a modified measurement setup and an optimized reconstruction algorithm, the challenges associated with high-resolution investigation of circuit boards with size restrictions by micro-CT were eliminated. Now, for example, control boards for automotive or power electronics and embedded systems can be analyzed non-destructively without any need for sample preparation.

Technical details

  • 225 kV microfocus x-ray tube
  • 2048 x 2048 pixel area detector
  • Spatial resolution: max. 900 nm
  • Specimen size: max. 60 cm (greatest extension), larger for examination of subareas
  • Sample weight: max. 6 kg

Application fields

  • Fast visualization of cracks in bond pads for electronic components on substrates
  • Examination of systems embedded in CFRP plates

X-ray diffraction

Fraunhofer IKTS utilizes the x-ray diffraction (XRD) method to determine the compositions of material mixtures. In this method, an incident x-ray beam is diffracted by ordered structures such as crystals or quasi-crystals and the diffraction intensity distribution is measured.

Fraunhofer IKTS also uses XRD to determine internal stresses via the sin2y method. Here, the specimen is tilted by a certain angle y (psi) to a reflection. Measurements are performed at various points, which at least include the extremes (edges, corners, and middle), to yield the distribution of internal stresses in the specimen. Texturing affects the results obtained by numerous methods. Using the sin2y method reliable values are determined, if the layer to be investigated is not textured. For this reason, the pole figures are obtained for at least two different reflections at various points on the test object. The internal stress can then be derived from the determined peak positions.

Application fields

  • Determination of compositions of material mixtures and internal stresses within the scope of materials and product development
  • Root cause studies for part defects

 

X-ray line detector

X-ray line detectors are usually used to examine continuous streams of products or to avoid undesired scattering when the object size only permits linewise illumination. The L100 line detector developed at Fraunhofer IKTS is made using customer-specific ASICs and thus enables low-cost fabrication and diverse configurations – with no size restrictions. The novel detector also works with direct conversion. This yields higher resolutions and speeds than are obtained with conventional detectors. Thanks to the single-photon counting mode, the x-ray photon energies can also be evaluated. This enables “dual energy” applications, in which differentiation is made between materials in terms of composition.

Technical details

  • Line length: 102.4 mm
  • Resolution: 100 μm
  • Energy range: 30–200 keV and 2–40 keV
  • Scan speed: up to 50 m/s

Application fields

  • In-line quality assurance and materials classification for:
  • Food and pharmaceutical industries
  • Small parts/semi-finished product manufacturing