Influence of phase shift on the responses of woven laminated composites

This paper focuses on understanding the influence of phase shift on the responses of woven laminates under uniaxial compression, uniaxial tension, biaxial compression, biaxial tension, and in-plane shear. Laminates in this paper have the same constituent microstructures in each layer of lamina. Fiber tows are modeled as transversely isotropic materials. Matrix is modeled as isotropic material before yielding and modeled as perfectly plastic material after yielding. All simulations are subject to periodic boundary conditions in the x and y direction whereas z direction, the through-thickness direction, is not subject to periodic boundary conditions. The results show that phase shift has significant influence on the homogenized tangential stiffness and the failure strength particularly under uniaxial compression. Under uniaxial compression, the laminate without phase shift has the lowest maximum strength and tangential stiffness and the laminates with 4 mm phase shift has the highest maximum strength and the highest tangential strength. Under biaxial compression, the laminate with 4 mm phase shift also has the highest maximum strength but the laminate with 2 mm phase shift has the lowest maximum strength. However, the tangential modulus do not change during the deformation under biaxial compression. The results show that by optimally arranging phase shift, the maximum strength for a laminate under uniaxial compression and biaxial compression can be reached.