Thermal buckling of thin injection-molded FRP plates with fiber orientation varying over the thickness

The different thermo-elastic properties of glass fibers and polymer matrices can generate residual thermal stresses in injection-molded fiber-reinforced plastic (FRP) objects. During cooling from mold to room temperature, these be relaxed by large deformations resulting an instability the unwarped configuration (i.e., buckling). This article investigates buckling thin FRP disks via analytical formulation based on Föppl-von Kármán theory. A novel extension our previous work is assumption cylindrical orthotropy with material parameters varying over disk thickness order account for dependency fiber orientation distribution. parameter generalizing anisotropy ratio homogeneous orthotropic introduced its relation occurrence periodicity discussed. done a skin-core-skin model, which core-to-total defined. For distributions typical disks, it found that there exists value no occurs. It also demonstrated first mode described generalized ratio, thus extending results obtained Improvements accuracy predictions experimental data available literature when using model are shown. Finally, we study between temperature propose expression dependence normalized ratio. Results FEM simulations used validate proposed expression, proving applicability accuracy.