Infrared Thermography During Bonding and Sealing
Precisely Testing the Quality of Joints Non-destructively
From the car body to the headphone – innovative material mixes made of modern fibre composites and well-tried metals are playing a more increasingly important role as materials in lightweight construction for industrial and household goods. The most varied composite fibre materials, such as carbon-fibre reinforced plastic (CFRP) and glass fibre reinforced plastic (GFRP), are combined with aluminium and magnesium as well as with high-strength and ultrahigh-strength steels. Joining such multi-material mixes imposes partially very high demands on the technology and manufacturers involved in this.
Bonding and sealing have established themselves as practicable joining technologies besides riveting, screwing and clinching. Thus, for example, the typical large contact surfaces facilitate the strength of large, thin lightweight composites for bonding. Consequently, components with less wall thickness and thus less weight can be installed. At the same time, the use of adhesives and adhesive tapes increases technological flexibility. Both can be processed manually and automatically. This opens up new possibilities for the production of single pieces as well as for serial production.
Detect and Exactly Localise Errors
Infrared thermography has already been used for years during bonding and sealing for monitoring and controlling technological parameters, such as the geometry of the adhesive application, adhesive temperature and adherend temperature as well as curing temperature.
Whether an adhesive joint actually has the required properties with regard to geometry of the adhesive area and adhesive bond, for example, can also now be tested by means of infrared thermography. The quality of the respective joint can be accurately tested non-destructively by means of images taken by a thermal and geometrical high-resolution thermographic camera. Certain methods of active thermography, such as lock-in thermography, have proven to be particularly suitable in practice. Thus, users have the possibility to characterise even more complex lightweight components, which consist of various structures and partially multi-layered material mixes.
The Following Types of Errors Can Be Detected by Using Thermographic Systems
- Errors regarding adhesive application, temperature of the adhesive and adherend temperature
- Shape/size errors as an indication of just partially joined components
- Errors in the temperature curve with conclusion based on e.g. the amount of adhesive used
- Position errors with reference to incorrectly positioned tools and joined parts
- Faults in the curing and cooling process as well as in the mould temperature control
- Material defects, cavities, inclusions, holes, etc.
Your Benefits at a Glance
- The use of high-quality thermographic cameras with detector formats up to (1,920 × 1,536) native IR pixels and a thermal sensitivity in the millikelvin range
- Specially designed INDU-SCAN software, based on application experience developed from a variety of industries
- All system components are suitable for rugged 24/7 continuous use in an industrial environment
- The use of various fieldbus interfaces such as Profinet, PROFIBUS, CC-Link
- Competent support from the feasibility study, including the development of the task and project outline right up to the preparation of a specification sheet
- Planning and implementation based on standardised solutions such as in Eplan, CAD, etc.
- Implementation and commissioning of turnkey solutions including briefing and training of staff
- Support and service from a single source
- Innovative measurement technology based on skills, which have been developed from more than 30 years of practical experience in the field of thermography