Fraunhofer Institute for Physical Measurement Techniques IPMMeasuring strain and deformation optically
Strain and deformation measurement play a vital role in the development, quality control and failure analysis of components. Fraunhofer IPM develops fast and robust measurement technology for materials testing that permits such deformations to be measured with micro- or even nanometer precision. The measurement systems are suitable for materials testing as well as for measuring machine parts or electronic components during operation.
Measuring deformations using Electronic Speckle Interferometry (ESPI)
Today’s electronic components, for example, heat up strongly due to their high power density, which can lead to mechanical stresses, deformations or microcracks – often resulting in component failure.
An optical measurement system developed by Fraunhofer IPM based on Electronic Speckle Interferometry (EPSI) measures minimal changes in component topography quickly, with imaging and down to the nanometer range – even directly in line – and thus provides valuable data for defect analysis.
Optical strain measurement by means of digital image correlation (DIC)
Strain-controlled fatigue tests under cyclic loading – e.g. low cycle fatigue (LCF) tests – are common practice when qualifying new materials such as lightweight materials for automotive or aircraft construction.
With an optical system based on the technology of digital image correlation (DIC), we are combining the advantages of previously available optical and tactile measurement methods in a single system – thus forming the prerequisite for fast, non-contact and marker-free strain measurement and control in real time.