U.S. Army Aerostructures Directorate, NASA Langley Research Center, Hampton, VA
Analytical Services and Materials, Inc., Hampton, VA
Pages: 22 Published: Jan 1993
This paper describes a technique to determine interlaminar tensile strength, σ3c of a fiber reinforced composite material using a curved beam. The specimen was a unidirectional curved beam, bent 90°, with straight arms. Attached to each arm was a hinged loading mechanism that was held by the grips of a tension testing machine. Geometry effects of the specimen, including the effects of loading arm length, inner radius, thickness, and width, were studied. The data sets fell into two categories: low strength corresponding to a macroscopic flaw related failure and high strength corresponding to a microscopic flaw related failure. From the data available, the specimen width and loading arm length had little effect on σ3c. The inner radius was not expected to have a significant effect on σ3c, but this conclusion could not be confirmed because of differences in laminate quality for each curve geometry. The thicker specimens had the lowest value of σ3c because of poor laminate quality.
composite material, carbon epoxy, interlaminar tensile strength, curved beam, delamination
Paper ID: STP12638S