Modelling and Experimental Investigation of Hexagonal Nacre-Like Structure Stiffness

Abstract

A highly ordered, hexagonal, nacre-like composite stiffness is investigated using experiments, simulations, and analytical models. Polystyrene and polyurethane are selected as materials for the manufactured specimens using laser cutting and hand lamination. A simulation geometry is made by digital microscope measurements of the specimens, and a simulation is conducted using material data based on component material characterization. Available analytical models are compared to the experimental results, and a more accurate model is derived specifically for highly ordered hexagonal tablets with relatively large in-plane gaps. The influence of hexagonal width, cut width, and interface thickness are analyzed using the hexagonal nacre-like composite stiffness model. The proposed analytical model converges within 1% with the simulation and experimental results.

Novel Method of Carbon Precursor Masking to Generate Controlled Perforations in a Carbon Film

“…This paper presented a novel method for the perforation and topological patterning of carbon-based material. The resultant perforated carbon films can be used to construct biomimetic platelet matrix composites similar to the structures described in the work of Sakhavand et al [10,11] and Rouhana and Stommel [12], and structures investigated by Behr et al [13,14] and Mirkhalaf et al [15]. Generating periodic porosity in brittle material also allows crack arresting and improves toughness [16][17][18].…”

“…Additional perforation geometries can also be produced by changing the PTFE clamp pattern, as shown in Figure 2. This geometry is inspired by bio-based Nacre material, with hierarchical high-stiffness hexagonal plates bonded by a high-plasticity matrix, resulting in a high-stiffness composite [12]. The acid is added between the clamps at room temperature and left for twelve to twenty-four hours depending on the film thickness so that the polymer film crosslinks in unmasked areas.…”

“…Generating perforated carbon films with an energy-efficient and accurate method could allow the construction of carbon platelet composites and carbon film laminates with varying properties and applications. Successful manufacturing of patterned carbon foils as described by Rouhana and Stommel [12] would allow the design of novel composites with potentially similar mechanical properties as carbon fiber composites.…”

Editorial for the Special Issue on Characterization and Modelling of Composites

“…Rouhana and Stommel [7] investigated a highly ordered, hexagonal, nacre-like composite stiffness using experiments, simulations, and analytical models. Polystyrene and polyurethane were selected as materials for the manufactured specimens using laser cutting and hand lamination.…”