Development of a combined mechanical-climatic rapid-aging procedure for structural wood-based materials (TimberAge)

04.05.2021

On 1^st May 2021, the IGF project 21822 N heralded the start of the “Development of a combined mechanical-climatic rapid-aging procedure for structural wood-based materials” (TimberAge). The research project, which is scheduled to run for three years, is being conducted at the University of Kassel, department of Trennende und Fügende Fertigungsverfahren (production processes for separating and joining), and at the Fraunhofer WKI.

In composite bonding, the anisotropic properties of wood pose different challenges compared to those of synthetic materials. The swelling and shrinkage of wood in response to changes in humidity, for example, and also chemical changes in the adhesive caused by differing wood constituents, must be taken into account, particularly with regard to the aging of the bond.

For the determination of the weathering stability and the aging behavior of wood-based materials in outdoor applications, var-ious established test methods, such as outdoor weathering tests and rapid-aging procedures, have been utilized so far. These procedures are, however, sometimes difficult for SMEs to implement. The duration of outdoor weathering is also too long for, e.g., the market launch of a new product. Rapid-aging procedures, in contrast, include drastic test parameters which do not necessarily correspond to the problematic nature of aging in reality. On the basis of the existing testing procedures, a test method is therefore to be developed which allows a better eval-uation of the failure patterns and, as a result, enables conclusions to be drawn regarding the aging behavior, the bonding and the processes, thereby taking into account the different influencing factors on both the adhesive side and the wood side.