Research on low-expansion metamaterial technique of four-leaf clover bionic structure

A new metamaterial structure has been developed with ultra-low expansion characteristics, featuring a unidirectional thermal expansion coefficient of less than 1 × 10−7/°C. Metamaterial structure is a new type of composite material designed artificially, by combining material technology with mechanical design technology, to achieve properties that cannot be achieved by conventional materials. Using the metamaterial design method, two materials with a large difference in thermal expansion coefficient are selected to design and realize the negative expansion unit structure. Combining the designed negative expansion structure and the conventional structure with positive expansion, the ultra-low expansion characteristics are finally realized through the mutual compensation of the thermal deformation properties of the two. The ultra-low thermal expansion characteristics of the novel metamaterial structures are verified through material modeling and simulation analysis.