The SKZ Plastics Center and the Fraunhofer IFAM are researching non-destructive testing methods for the quality assurance of sealants in the IGF research project "SteP-in". Thanks to their comprehensive functions, sealants have many areas of application. However, the curing time specified by the manufacturer is often relied upon during application or complex in-process measurements are carried out. This involves additional work or unnecessarily long holding times before the next process steps.
Use of air ultrasound and optical profilometry
To enable a more efficient process, the SKZ and the Fraunhofer IFAM are currently researching non-contact testing methods that can be used to determine the curing progress inline. Air-coupled ultrasound, or air ultrasound for short, and optical profilometry are being used for this purpose. Air ultrasound can be used to determine changes in the density or elastic properties of the sealant, while optical profilometry can measure shrinkage during curing with a resolution in the µm range.
Training artificial intelligence
The measured variables are to be used together with other influencing factors to train an artificial intelligence. Curing models can be created with which a reliable determination of the curing progress is possible. Furthermore, a measurement method is to be developed that can be used to detect typical defects such as air inclusions or detachments in the seals. A measurement approach based on active thermography is being further developed for this purpose.