Step by step to a high-quality bonded joint!

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We assist you with all steps of the development work!

The first step is classification of the bonded joints into safety classes based on the consequences of joint failure. For this we use methods such as Failure Modes and Effects Analysis (FMEA). The safety class determines how the calculation and verification must be performed.

The next step involves specification of the substrates. Besides specifying the properties in the as-supplied state, the structure and behavior under stress must be defined. With regards to the state of the surface, aspects such as surface pretreatment (e.g. sanding, plasma pretreatment) and quality assurance measures must be specified.

In addition, the requirements on the bonded joint must be determined. The following applies here: The more accurately the real requirements are determined, the more accurately the design of the bonded joint can be undertaken. The bonding areas, the position, and the size of the bonded joint must be specified.

In order to select a suitable adhesive, the particular application area and environmental influences must be considered as must the production conditions. For the verification it must be demonstrated that the adhesive adheres to the substrates even after aging. It must also be demonstrated that the loads on the bonded joint are lower than the load limit of the bonded joint. In order to prove this, the loads acting on the bonded joint are calculated and compared to values recorded in tests on standardized test specimens and on real components.

Besides providing assistance with the design of bonded joints, Fraunhofer IFAM also develops surface pretreatment methods and measurement technology to meet your needs.