Strength characterization of woven glass/epoxy composites under tensile fatigue loading at cryogenic temperatures using open hole specimens

In this article, we investigate the strength characteristics of woven glass fiber reinforced polymer composite laminates subjected to tensile fatigue loading at cryogenic temperatures using the open hole specimens. Tension-tension fatigue tests were conducted on the open hole specimens of the woven glass fiber reinforced polymer laminates at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K), and microscopic observations of damage around the hole were made on failed specimens. A numerical procedure based on the finite element method was then applied to evaluate the fatigue strength of the unnotched woven glass fiber reinforced polymer laminates using the experimentally applied load and the length of the hole edge damage zone. The obtained results were compared with the existing experimental data from the unnotched specimens. It was demonstrated that the presented combined numerical-experimental method was effective for the determination of the fatigue properties of the woven glass fiber reinforced polymer laminates at cryogenic temperatures.