Materials and structures with auxetic and negative linear compressibility are of great potential to be used in many
applications because of their uncommon mechanical deformation features. However, their design and manufacture are
less studied as compared to other mechanical properties. The aim of this research is to explore several new approaches
relating to the design and fabrication of cellular materials and structures with these two uncommon features. For most
cellular materials and structures, these uncommon properties only exist for a limited geometric range. To begin with, the
geometric limit of the microstructure of a 2D elastomer-based auxetic material was identified numerically through large
deformation analysis. Within the geometric limits, a tuning method was developed further to control their mechanical
properties with prescribed performance constraints. A metallic auxetic metamaterial was used as an example of the
developed tuning approach, and its effectiveness was validated by experimental results with specimens manufactured
using 3D printing technique.To reduce the manufacturing cost using 3D printing, a composite approach was proposed to
manufacture these metamaterials. Several new cellular composite structures with negative linear compressibility
composite structures were used as examples to demonstrate the effectiveness of the design approach. The test samples
were manufactured using the traditional composite method with low cost. These investigations mentioned above have
clearly demonstrated the feasibility of designing and manufacturing of mechanical metamaterials using the presented
approaches and laid the foundation for the expansion of their potential applications.
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