3.2 Load types
Compressive and tensile stress / load
These forces act perpendicular to the bonding area.
In principle unproblematic, but the bonding area is often too small.
The force acts parallel to the bonding area.
Bonded joints should be designed for this force.
Line shaped stress, namely the force acts along the bond width.
Peel stress must be absolutely avoided!
Types of stresses/loads:
- Mechanical stresses (uniaxial or multiaxial)
- Static (shear, compressive, tensile, and torsional stresses)
- Cyclical stress
- Shock, impact and crash loads
Cyclical stress: Cyclic repetition of a specific mechanical stress
Although even a single load can lead to damage to the adhesive, multiple cycles with the same load are more likely to cause damage (material fatigue).
Can have different effects depending on the intensity (deflection (amplitude) and number of cycles (frequency)), direction and the nature of the bonded joint.
Impact stress: Arises due to the acceleration or retardation of masses; usually no regular repetition.
Can have different effects depending on the intensity (force and speed), direction and the nature of the bonded joint.
Media loads: These include chemicals such as cleaning agents and also moisture. Important factors are the duration of action, temperature and in some cases the concentration of the medium.
Radiation: Usually natural UV radiation, but in special cases x-rays or other radioactivity.