Effect of fiber length on the tensile strength of unidirectionally arrayed chopped strands. (2nd January 2020)

• Record Type: Journal Article
• Authors: Taketa, I.; Matsutani, H.
• Is Part Of: Advanced composite materials. Volume 29:Number 1(2020)
• Page Start: 43
• Page End: 54
• Publication Date: 2020-01-02
• Subjects: discontinuous fiber composites -- tensile strength prediction -- fracture mechanics -- delamination -- unidirectionally arrayed chopped strands; Composite materials -- Periodicals; Reinforced plastics -- Periodicals; Electronic journals; 620.11805
• DOI: 10.1080/09243046.2019.1650321
• Languages: English
• ISSNs: 0924-3046

Abstract

Abstract : This study investigates the effect of fiber length on the tensile strength for discontinuous fiber composites. A composite with a staggered structure of fiber bundles were prepared by stacking prepreg sheets with unidirectionally arrayed chopped strands with a predetermined fiber length. The sheets were prepared by introducing fine slits at regular intervals along the fiber direction. The final failure is caused by an unstable growth of delamination from the tip of the bundles. The conventional linear fracture mechanics model cannot explain the reduction in the tensile strength as the fiber length shortens. Consequently, this paper proposes a novel fracture mechanics model that considers a non-linear stress–strain relation for the composite, which incorporates varying fiber length. The results confirm that this model can explain the relation between the tensile strength and fiber length very well, without any fitting parameters.