Mycelium-Based Composites as Two-Phase Particulate Composites: Compressive Behaviour of Anisotropic Designs.

Abstract

Mycelium Based Composites (MBC) exhibit many properties that make them promising alternatives for less sustainable materials. However, there is no unified approach to their testing. We hypothesise that the two-phase particulate composite model and use of ASTM D1037 could provide a basis for systematisation. An experimental series of MBC were produced using four substrate particle sizes and subjected to compression testing. We report on their effect over Young’s modulus and ultimate strength. We extend the study by investigating three anistropic substrate designs through orientated fibre placement as a strategy for modifying compressive behaviour. We find that the two-phase particulate model is appropriate for describing the mechanical behaviour of MBC and that mechanical behaviour can be modified through anisotropic designs using orientated fibres. We also confirm that fibre orientation and particle size are significant parameters in determining ultimate strength.

Effect of Composition Strategies on Mycelium-Based Composites Flexural Behaviour

“…Similarly to our previous investigation on compression behaviour characterisation [ 10 ], the hessian jacketing series offers a contrasting instance of the effect that the cultivation of an external mycelial skin on test specimen might lead to. The BM_H series resulted in a 1.95-fold increase in flexural modulus as compared to the control group, and 1.5-fold increase in strength.…”

“…Composition strategies by arming or particulate design are therefor a scarcely studied area of material development still, while the lower stiffness of the mycelial matrix (the tensile modulus of Pleurotus ostreatus and Ganoderma lucidum species is reportedly in the 4–28 MPa range [ 8 ]) as compared to, for instance, American beech wood ( Fagus grandifolia ) elastic modulus of 11.9 GPa at 12% moisture content (MC) [ 9 ], suggests that the design of the composite dispersed phase can considerably influence the final composite mechanical stress response. The significance of composition strategies over the composite compressive behaviour has been reported previously, both for aggregate size and fibre placement [ 10 ].…”

AM Perspectives: Research in additive manufacturing for architecture and construction

“…To an extent, the material contrasts achieved through such placing processes can also foster new aesthetics, an aspect explored both in the Printsugi project, confronting clay and stone, and in the PRINT!Architecture studio, confronting wood and clay. The frailty and refinement of details investigated here, contrasted with the rawness of materials chosen, can become a carrier for the new materials stories needed (Rigobello & Ayres 2021). The design details act as a means of value creation, highlighting a role for architects and designers that cannot be held by others.…”

Challenges and Opportunities in Scaling up Architectural Applications of Mycelium-Based Materials with Digital Fabrication

“…This results in an undesirable surface finish and inadequate geometric precision. Furthermore, because MBC are anisotropic materials [ 47 ] with a structural performance that is stochastic [ 48 ], this method of fabrication then has the potential to aggravate the structural performance and material characteristics of the block in an unpredictable manner. Some fungal strains, for example, develop a skin (seen in white in Figure 4 ), and this skin increases the material’s compressive strength as well as its water repellence [ 32 ].…”