Composite materials offer attractive features such as high specific strength, specific stiffness, and improved energy absorption in an impact event which makes them an excellent choice for use in structural and automotive applications. In addition, composite materials provide an unique manufacturing advantage of reducing part count as they can be used to build large monolithic components. However, the challenge of using composite materials is the multifaceted thermo-mechanical behavior exhibited by the resulting structures. One such complex behavior is the springback deformation in unidirectional laminates that develops during the manufacturing process. Composite structures are cured at elevated temperatures (～177°C) and then cooled down to ambient temperature (～25°C). This cool-down event induces deformation governed by the lamina properties and the laminate layup configuration. Furthermore, stresses can arise in the constituents (the fibers and the matrix) due to a mismatch in thermoelastic properties. The focus of this paper is to analyze the springback in a composite part during the cool-down event using advanced Finite Element Analysis (FEA). The intent is to examine modeling methodologies that can capture the structural deformation and investigate the constituent multiaxial stress state. A method for utilizing the calculated springback deformation to modify the original mold of the composite so that the final room-temperature shape of the composite is the "as designed" shape is also presented.
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