Abstract
Fatigue tests were performed on short glass fiber-filled, glass bead-filled and smaller particulate inorganic filled reinforced nylon 6, 66 castings at 100°C. The mechanisms of fatigue crack initiation and propagation were investigated through the fractography using SEM. The main results obtained are as follows; (1) The fatigue strength of filler reinforced nylon 6, 66 castings at 100°C are greatly influenced by the kind of fillers in particular, nylon 66 filled with glass fibers and smaller particulate inorganic fillers showed a maximum value of 107σw as 15 MPa. Conversely, nylon 66 filled with glass bead showed the minimum value of 107σw as 5 MPa. (2) The above results could be interpreted from the micromechanism of fatigue fracture appearing through the micromorphology of fracture surfaces as follows. the debonding between the nylon matrix and glass fibers has a very high quality, which is caused by the high ductility of nylon.
