Elastic–plastic behavior of woven-steel-fiber-reinforced thermoplastic laminated plates under in-plane loading

This paper deals with elastic–plastic stress analysis of thermoplastic laminated composite plates reinforced with woven steel fibers and containing circular holes under in-plane static loading. Residual stresses and propagation of plastic zones are obtained in simply supported symmetric and antisymmetric laminated composite plates by using a nine-node Lagrangian finite-element method. First-order shear deformation theory was used as an equivalent single-layer laminate theory for small deformations so that large plastic strains are not allowed to occur. A modified Newton–Raphson method is used as an iterative technique for determining the non-linear behavior of the material after yielding. After yielding the load is increased by means of many load steps, 0.01 MPa at each step, to follow the stress/strain curve more accurately. Mechanical properties of a layer were obtained experimentally.