Thermo-mechanical buckling analysis of symmetric VAT composite laminates with temperature-dependent material properties

The thermo-mechanical buckling analysis of a Variable Angle Tow (VAT) laminate under uniform temperature rise and uniform end shorting displacement is performed in this paper. The orientation of the fibre is assumed to vary linearly along the length of laminate and the material properties of composites are considered to be temperature dependent. Based on the First-order Shear Deformation Theory (FSDT), the basic equation of buckling problem of VAT laminate is established and the nonlinear governing equations are solved by employing the Chebyshev-Ritz method and an iterative process. Numerical results of the critical buckling temperature of VAT laminate are compared with those existing and the accuracy of the solutions is validated. The effect of temperature-dependence of material properties, different fibre paths and different boundary conditions on the critical thermo-mechanical buckling load is discussed in numerical examples. It is found that there is great influence of the temperature-dependence of the thermal expansion coefficients on critical buckling temperature of VAT plate. For different boundary conditions, the approximate relations among the critical buckling temperature and the fiber angles at the edge and at the center of the plate are given based on the numerical results. The critical buckling temperature of VAT laminate can be improved by properly selecting the fibre paths. For the thermo-mechanical buckling problem, the critical buckling temperature monotonously decreases with the increase of uniform end shorting displacement. The investigation presented here may be helpful for the design of VAT composite laminate.