Thermoelastic design of symmetric laminates using lamination parameters

An effective laminate design method is shown for thermoelastic properties of symmetric laminates with extension-shear or bending-twisting coupling. The relationship between thermoelastic properties and laminate configurations is examined by using lamination parameters which can express any laminate configuration. The coefficient of thermal expansion (CTE) is represented on the lamination parameter plane. The graphical representation clarifies the effect of laminate configurations on the CTE. It is shown that the CTE of graphite/epoxy composites can be controlled in a wide range from positive to negative values by tailoring laminate configurations. Thermal deformation characteristics of symmetrically laminated plates are also examined using lamination parameters for simply supported plates under two temperature conditions. An optimal laminate design of symmetrically laminated plates for thermal deformation is shown based on a mathematical programming method where four lamination parameters are used as design variables.