Mycelium-metal hybrids: Exploring fabrication and application for reconfigurable design structures

Mycelium-bound composites (MBCs) are materials grown by fungi onto lignocellulosic substrates. MBCs are a low-cost, lightweight, valorised biomass with promising properties concerning acoustics, heat insulation and fire resistance, among others. These properties make MBCs interesting as a sustainable alternative to currently existing fossil-fuel-derived products. However, MBCs lack properties such as mechanical strength or other functional properties like electrical conductivity which could widen their range of applications. In this work, the mycelium from Pleurotus ostreatus is grown in presence of metals. First, a coating strategy is developed to grow the fungus on aluminium, copper, and stainless-steel surfaces. The coating is made of agar and cornstarch to provide nutrients for the fungus to grow. It is found that the mycelium can grow on all surfaces, even on anti-bacterial copper surface. Secondly, magnetic MBCs with 3D shapes are fabricated for making potential reconfigurable structures. For these composites, the fungus is exposed to lignocellulosic substrate and rare earth magnets. Using 3D printing to create 3D moulds to grow the composite, and by strategically placing the magnet, several structures are made. This approach is interesting for the future design and fabrication of reconfigurable panels for room partition, building thermal or insulation, or to replace plastics in toy products, among others.