Aflaminering

Aflaminering, or delaminering, is a failure mode in laminated materials in which individual layers detach from each other along the interfaces. This separation reduces the ability of the structure to transfer loads, and it can also compromise insulation, barrier properties, or optical performance, depending on the application. Aflaminering is commonly discussed in relation to plywood, fiber-reinforced polymer laminates, and laminated glass, as well as other multi-layer composites.

Causes and mechanisms vary but often involve interlaminar stresses and environmental or mechanical factors. Moisture ingress, temperature cycling, UV exposure, chemical attack, or aging can weaken the adhesive or resin between layers. Manufacturing defects, improper surface preparation, or mismatched materials can create weak interfaces. Impact damage or repeated cyclic loading (fatigue) can initiate and propagate delaminations from existing flaws. In laminated glass, delamination may occur at the glass–interlayer interface due to prolonged exposure, thermal stress, or excessive bending.

Signs of aflaminering include visible cracks between layers, edge lifting, bubbling, or a general loss of stiffness and dimensional stability. Non-destructive inspection methods such as ultrasonic testing, infrared thermography, or acoustic emission monitoring can help detect hidden delaminations, while mechanical tests can quantify interlaminar strength.

Prevention focuses on proper material selection, surface preparation, and manufacturing control. Maintaining appropriate environmental conditions, moisture barriers, and compatible adhesive systems helps reduce risk. Repairs may involve removing and replacing affected layers, injecting resin into cracks, or applying patches or overlays, depending on the material and extent of the delamination. Standards for testing often address mode I and mode II delamination and non-destructive evaluation techniques.