A new methodology to evaluate the influence of curing overheating on the mechanical properties of thick FRP laminates

Polymeric composite parts are often manufactured with thin laminates and the manufacturer's recommended cure cycles are usually optimized for a less than 5 mm thickness. However, sometimes manufacturing thick laminates is necessary for structural applications: in this case, the manufacturer's cycle is not suitable as it can produce a peak of temperature in the laminate, which may compromise the structural integrity of the product. This work aims at quantifying both the magnitude of these peaks and its effect on the mechanical properties of the cured material through numerical and experimental tests. A decrease of the interlaminar shear strength with increasing temperature peak was found, while the duration of temperature peak did not influence the structural strength of the resin.