Fracture behavior of G-10 woven glass-epoxy laminates at low temperatures

We discuss the low temperature fracture behavior of G-10 woven glass-epoxy laminates. Plane-strain fracture toughness tests were carried out with compact specimens (width to thickness ratio W/B = 2.5) at room temperature, 77 K and 4.2 K to evaluate the fracture toughness and the temperature rise of G-10 woven glass-epoxy laminates. Au-Chromel thermocouples were used to measure the temperature rise. The tests were conducted in accordance with ASTM Method E399. The influence of the crack length and loading rate on the low temperature fracture behavior is shown graphically. The temperature rise near the crack tip is correlated with the amount of crack extension and loading rate. SEM micrograph shows the complicated structure of the damage zone near the crack tip (broken and delamination fibers, fiber pull-out, broken epoxy resin)