Shear Fracture Tests (Mode II) on Fiber Reinforced Plastics at Room and Cryogenic Temperatures

Abstract

Because of their excellent mechanical properties at low temperatures glass-fiber reinforced plastics have been used for an increasing number of applications. Hence, the assessment of their mechanical properties at low temperatures under various loading conditions (tension, compression and in particular shear) have become of special interest. In the present contribution, we report on a new (experimentally simple) method designed to measure the shearing properties and the fracture behavior in mode II on notched rectangular specimens, which is especially well suited for measurements on small samples, e.g. for irradiation experiments. Results on a two dimensional reinforced epoxy (ISOVAL 10), which were obtained at room temperature and at 77 K, will be presented. The fracture-mechanical characterization of the material in mode II (shear mode) will be treated as a limiting case of the new testing method. Results of acoustic-emission investigations as well as data pertaining to variations of the shear area will be discussed. Advantages and disadvantages of this new technique will be assessed and compared to other shear test methods.