Experimental identification of process parameters inducing warpage of autoclave-processed CFRP parts

Autoclave processing of reproducible carbon fibre reinforced plastic (CFRP) structures with high dimensional fidelity is a main challenge for today’s composite manufacturing within the aerospace industry. An ex ante geometrical tool compensation as well as an appropriate process control to minimise dimensional variations requires a good understanding of the crucial parameters. In the present paper a wide range of experimental investigations affirm that warpage deformation of symmetric and initially flat laminates is mainly driven by mechanical tool–part interaction. Furthermore, tool surface roughness and interleaved neat resin areas are observed to influence the magnitude of these deformations significantly. For the description of the effective mechanism a new model, accounting for these findings, is proposed.