Cryomechanics and Double-Notch Interlaminar Shear Strength of G-10Cr Glass-Cloth/Epoxy Laminates
We discuss the interlaminar shear behavior of G-10CR glass-cloth/epoxy laminates through experimental and analytical characterizations. The interlaminar shear tests were carried out with double-notch shear specimens at room temperature, 77K and 4K to evaluate the interlaminar shear strength (ILSS) of G-10CR glass-cloth/epoxy laminates. The double-notch shear specimen was loaded on its ends in compression with a supporting jig to prevent buckling. These tests were conducted in accordance with ASTM D3846-79. The effects of temperature, specimen thickness and notch separation on the apparent ILSS are shown graphically. Fracture surfaces were examined by scanning electron microscopy (SEM) and optical microscopy to verity the failure mechanisms. A three-dimensional finite element analysis was also performed to investigate the effect of specimen thickness and notch separation on the shear stress distribution in the expected fracture plane. Effective elastic moduli were determined under the assumption of uniform strain inside the representative volume element. The numerical findings are then correlated with the experimental results.
KeywordsRepresentative Volume Element Specimen Thickness Fracture Plane Shear Stress Distribution Interlaminar Shear Strength
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