Cryogenic interlaminar shear strength of G-10 CR glass-cloth/epoxy laminates by the short-beam method.

Interlaminar beam tests in the form of three-point flexure were examined both experimentally and analytically. The short-beam shear tests were carried out at room temperature, 77 and 4 K to evaluate the interlaminar shear strength of G-10 CR glass-cloth epoxy laminates. These tests were conducted in accordance with ASTM D2344-84. The effects of temperature, specimen width and span-to-thickness ratio on apparent interlaminar shear strength are shown graphically. Photomicrographs (scanning electron micrographs, optical micrographs) of actual failure modes were utilized to verify the failure mechanisms. A three-dimensional finite element analysis was also performed to investigate the effects of specimen width and span-to-thickness ratio on the shear stress distribution in the mid-plane of the beam.