Thermally-Induced Deformation of AsymmetricComposite Laminates

摘要

A new method is presented to predict the nonlinear warpage of large composite panels after cure.rnNonlinear strain-displacement relationships in the von-Karman’s sense is assumed. By assuming thernmid-plane strains and curvatures are independent of locations for a large panel, the authors provernthat the compatible panel shapes must have zero Gaussian curvature and are therefore cylindrical.rnApplication of potential energy principle with Lagrange’s multiplier results in equations needed torndetermine the magnitude and principal direction of the cylindrical shapes. The stiffness matrices ofrncomposite laminates from classical lamination theory are retained so that proper dimensions suitablernfor lamination theory are presented in the formulation. Results of anti-symmetric angle-plies arerndemonstrated and found to be consistent with results of other investigators. The two well knownrnstable cylindrical shapes are proven to have opposite signs of both curvatures and principalrndirections for anti-symmetric angle-plies.