Experimental study on axial compressive properties and failure mechanism of unidirectional covered carbon fiber-reinforced polymer composites

Abstract

Axial compression performance is one of the main factors considered in the structural design of fiber-reinforced composites. However, the properties of the fibers in such composites are poor because of their orientation structures. Here, filament fibers were covered with reinforced fiber bundles to improve the axial compressive properties of the composites, and the effects of fiber covering on the axial compressive properties and failure modes of the composites were studied. The experimental results show that the covering can shorten the buckling wavelength of carbon fiber under compressive load, which can effectively improve the axial compression ability of the composite. A lower modulus of the covered filament reduced the potential to improve the compressive strength of the samples, and damage occurred primarily by splitting and shearing. With an increase in the covering density, the compressive strength and modulus gradually increased, and the damage mode changed from flexural instability to kinking damage.