Bimaterial lattices with anisotropic thermal expansion consist of nonidentical cells
comprising a skewed triangle made of one material surrounding an unskewed triangle
made of a second material. The two materials have differing individual coefficients of
thermal expansion. The variation in skew angles makes the thermal expansion of the
cell anisotropic. Being composed of anisotropic nonidentical cells, the assembled
lattice is also anisotropic and can be designed to have different coefficients of thermal
expansion on its top and bottom surfaces. Such lattices can be used as transition
elements or adapters to avoid thermal-expansion mismatch between two
parts of a structure made of materials with different coefficients of thermal
expansion and subjected to temperature changes. In the present paper, three
nonlinear algebraic equations linking skew angles with the coefficients of thermal
expansion in three directions of a cell are derived, the design of several lattices is
performed, the algorithm of lattice design is elaborated, and some examples are
presented.
Keywords
composite lattices, graded coefficient of thermal
expansion, thermal-mismatch adapters