Fatigue performance of composite laminates after impact

Important results from the project

Thin-ply composites have recently been receiving significant interest in the composite industry. By reducing the ply thickness an increase in transverse tensile and shear strength is obtained. Damage resistance for an impacted laminate during fatigue has been evaluated within the project. Without changing any materials, just by arranging the materials as a hybrid laminate with a mix of traditional prepreg and thin-plies, the maximum fatigue strain could be increased with more than 30%.

Expected long term effects

A hybrid layup of thin- and thick plies is more cost effective than a full thin-ply layup, the results show that replacing few layer of traditional prepreg by few layers of thin ply composite we can increase the fatigue limit by 30%. The results enables Oxeon to widen its market segments to a range where full thin ply layup is not an option.

Approach and implementation

The manufacturing of the three composite laminates, preparation of samples and impacting was all done by RISE Sicomp. Fatigue tests of the impacted specimens and ultrasonic inspection were performed at Linköping University. A great knowledge was gained during this project on how to work with thin-plies during manufacturing, how to cut the specimens and how to measure strains during the tests. Regular meetings were planned between all partners to share the knowledge and discuss research questions.