Analysis of process-induced deformation on the spring-in of carbon fiber-reinforced polymer thin laminates

The cure process of carbon fiber-reinforced polymer laminates induces residual stress inside the parts that causes geometrical unconformities. The most important unconformity is the spring-in that means the deviation of the flange-to-flange angle from the design angle. The spring-in value depends on some process parameters, such as the lay-up sequence of the plies, as demonstrated in previous works. The aim of this work is to study the dependence of the spring-in on the deviations in the orientation of the plies due to a hand process. A numerical tool was developed and experimentally tested.