Promoting sustainability based on the use of renewable raw materials has been a top priority for the Wilhelm-Klauditz-Institut (WKI) - also known as the Fraunhofer Institute for Wood Research - for over 70 years. Based in Braunschweig, the institute conducts research into process engineering, natural-fiber composites, wood and emission protection, quality assurance for wood products, recycling procedures, material and product testing, and the utilization of organic building materials and wood in construction - all through the lens of sustainability. WKI is at LIGNA 2019 with a wide-ranging showcase, including innovative hybrid materials made from renewable raw resources for applications in the mobility sector.
The institute is exhibiting the rib cross-section of a sporty, 22-meter-long sailing catamaran on a scale of 1:2 to show visitors exactly how sustainably produced, CO2-storing materials can be used systematically in a lightweight structure designed for automated production. When compared to standard plywood designs, the hull's stiff, lightweight sandwich structure reduces the amount of material used and with it the weight of the components, which are made of wood veneer, flax fibers, cork and vegetable-oil-based epoxy resin. As a result, only the hardener for the resin and a few auxiliary materials are derived from crude oil. The hull structure of the second exhibit - the hull cross-section of a small pedal boat with a pedelec drive - has to withstand much less stress and strain than the catamaran. This shifts the priority onto the use of particularly lightweight materials and low wall thicknesses. That is why two thin veneer layers, overlapping at 90° and with a total thickness of 1.6 mm, and a sandwich core made of recycled PET bottles are used for the outer surface layer, instead of industrially produced plywood. Meanwhile, the inner layer is made of flax-fiber laminate.
The third and final exhibit is an electric cargo bicycle that shows how aluminum can be replaced by renewable raw materials. As on the catamaran, structural components of the bicycle have been replaced with sustainably produced, CO2-storing materials. Unlike other bicycle frames made from renewable raw materials, this exhibit is compatible with a high level of production automation, thanks to its use of industrially manufactured plywood and assemblies that have been prefabricated in CNC processing machines.