Deformation induced from the orthotropy in the coefficients of thermal expansion(CTE) and the chemical shrinkage of matrix was studied for thermosetting polymer matrix composites. The maximum thermal deflections in out-of-plane direction and the stress free temperatures are found for various unsymmetric laminates. The stress free temperature is not consistent with the curing temperature of a laminate and strongly affected by matrix volumetric shrinkage. Finite element analysis of rectangular laminates was performed with consideration of the orthotropy in thermal properties using the commercial FEM code, ABAQUS. Deformation of L-shaped laminates after curing process was studied. The angle changes in L-shaped laminates with various thicknesses and lay-up angles were measured by using a gap sensor. Finite element analysis considering the difference in CTE's between thickness and radial directions was perfomed with ABAQUS. The contribution of the orthotropy in CTE's on the deformation of L-shaped laminates is small. Other causes of deformation in L-shaped laminates must be studied for the exact prediction of angle changes after curing process.
