The Role of Phase Shifts on Homogenized Modulus and Maximum Strength of Woven Laminated Composites

Abstract

This research focuses on responses of 64 woven laminated composites whose phase shift in microstructure is different under uniaxial compression and biaxial compression. The motivation of this paper is to understand how the microstructure arrangement affects laminate responses, particularly on the maximum strength and the tangential stiffness. Each laminated composite consists of four layers of laminae. Each layer of lamina has the same constituent microstructures. The laminae in different layers are shifted in the x and y direction to create phase shift. The first (bottom) layer of lamina in laminates remains stationary while the second layer of lamina, third layer of lamina, and fourth (top) layer of lamina are shifted in the x direction by 0mm, 2mm, 4mm, and 5mm, respectively. The results show that, under uniaxial compression, phase shift has significant influence on the homogenized tangential stiffness and has significant influence on the maximum failure strength. Under biaxial compression, phase shift also affects maximum strength. No significant difference on the tangential modulus of different laminates is observed under biaxial compression. By optimally arranging phase shift, the maximum strength of laminates under uniaxial compression or biaxial compression can be reached. For laminates consisting of the same microstructures in each layer of lamina, merely using homogenized modulus obtained from one layer of lamina cannot predict the responses of multi-layer-laminae composites due to phase shift.