Considerations on the incremental forming of natural fibre-reinforced polypropylene composites

Incremental sheet forming, originally developed as an excellent alternative to other material forming procedures for incrementally deforming flat metal sheets into complex threedimensional profiles, has recently been extended to polymers and composites. This work presents an experimental study on the incremental forming of natural fibre-reinforced polypropylene composites. Natural fibres for polymer reinforcement are gaining increased attention as fillers and competitive reinforcement materials. Cone frusta with fixed wall angles were manufactured to investigate the formability of composite sheets made from polypropylene reinforced with hemp and flax long fibre fabrics. Failures and defects were observed, and the forming forces during the process were monitored to draw conclusions on the feasibility of incremental forming applied to these composite materials.