Cooling rate influence on the warp of a CFRP asymmetric laminated beam

Abstract

This paper describes the age-related warp of carbon fiber reinforced plastic (CFRP) asymmetric laminated beams due to the viscoelasticity, anisotropy, and nonhomogeneity of CFRP laminates. Asymmetric orthogonally laminated CFRP beams held at a high curing temperature were cooled at various rates with and without constraints against warping during cooling. Furthermore, the warping of CFRP beams with the constraint lifted after cooling was measured during the aging processes. The age-related warping generated under various conditions was predicted using the viscoelastic and thermal properties of the CFRP laminates. The results were compared with measured data. The results were interpreted as follows. The age-related warping of CFRP beams depends strongly on the process conditions of the cooling rate and constraint, and the thermal and physical age-related shrinkage and viscoelasticity in the transverse direction of unidirectional CFRP affect the age-related warp of CFRP beams. Thermoviscoelastic analysis with physical age-related shrinkage is effective for this prediction.