Plastics, adhesives and sealants can be analyzed and characterized non-destructively. For this application, Fraunhofer EZRT together with the company Pure Devices GmbH has developed a dedicated mobile MR system which, in combination with our software specially adapted to the problem, offers ease of use and simple evaluation. The objects or samples are examined in the magnetic field using high-frequency radio waves without the need for time-consuming preparation.

Figure 1: Fraunhofer Polymer-Profiler in cooperation with Pure Devices GmbH.
Figure 2: 2D fingerprints to distinguish between different polyurethane samples.

Relaxometry measures the material characteristic parameters (MR relaxation time constants) T1, T2 and T2*. Smallest changes in relaxation times, such as those that occur during curing or drying processes, can be monitored almost in real time, so that the measurement method can be used with the Fraunhofer EZRT Polymer-Profiler not only for quality control, but also inline for adjustments.

For the characterization of materials, the 2D fingerprint measurement method offers further advantages. From the material characteristic parameters, maps can be made whose patterns are unique, similar to that of a fingerprint. By correlating the T1 and T2 relaxation patterns, materials can be identified and material changes can be visually tracked.

© Fraunhofer IIS
Figure 3: Projections of a 2D fingerprint onto its axes yields the underlying T1 and T2 spectra.