Elasto-plastic stress analysis in simply supported thermoplastic laminated plates under thermal loads

In this study, an elasto-plastic stress analysis is carried out on symmetric cross-ply [0°/90°]2 and symmetric angle-ply [30°/−30°]2, [45°/−45°]2, [60°/−60°]2 thermoplastic laminated plates. Laminated composite plates are simply supported and subjected to constant temperature change through the thickness. An analytical solution is performed for satisfying thermoelasto-plastic stress/strain relationships and boundary conditions for small plastic deformations. The composite materials are assumed to be perfectly plastic. The Tsai-Hill theory is used as a yield criterion. Residual stress components, View the MathML source and View the MathML source, for cross-ply laminated plates have some magnitudes but View the MathML source are zero. The magnitudes of residual stress components increase gradually depending on the temperature increment. For symmetric angle-ply laminated plates, residual stresses are found zero except View the MathML source.