Failure Mode Transition in Unidirectional E-Glass/Vinylester Composites under Multiaxial Compression

Results from an experimental investigation on the mechanical behavior of a unidirectional fiber reinforced composite with 50% volume fraction E-glass/vinylester and the vinylester matrix under uniaxial and proportional multiaxial compression are presented. The stress-strain curve and the acoustic emission records together with the post-mortem observations on the specimen show the failure mode transition from axial splitting to kink band formation as the loading condition changes from uniaxial to proportional multiaxial compression. Axial splitting and "splitting induced" kink band formation were observed in the uniaxially loaded specimen and the multiaxially loaded specimen showed conjugate kink bands and no axial splitting.