Failure of specimens of carbon fiber-reinforced epoxy plastics in static and fatigue loading

Abstract

1. The carbon fiber-reinforced epoxy plastic with the examined lay-ups of the reinforcing fibers is characterized by higher fatigue failure resistance than the metals and glass fiber-reinforced plastic. 2. The load-carrying capacity of the specimens of the carbon fiber-reinforced plastic is not exhausted by the appearance of the first damage. Macrofailure is preceded by the large reduction of the stiffness of the specimen; this may be utilized in inspecting and predicting failure. 3. Appearance of the cracks in the vicinity of the notch does not cause premature macrofailure of the specimens; the strength of the specimens with the notch may be evaluated approximately from the strength of the unnotched specimens, taking into account the notch area. 4. The results of the measurements of acoustic emission and temperature to which the carbon fiber-reinforced plastic is heated can be used to assess damage cumulation and to predict transition to macrofailure.