Ichiji Obinata

Effects of constituent particles on ductile type striation

Continued from the previous report on fatigue fracture topography in aluminum alloys, this paper discusses on the effects of constituent particles in ductile striation structure on the rate of fatigue crack propagation by the observation of electron fractography.As the results, even if the width of plastic zone at the crack tip was larger than the spacings between the particles arresting effects were observed under various conditions as well as accelerated effects of the constituent particles on the crack propagation, which had been pointed out by Piper3)and Pelloux4).The effects of constituent particles on fatigue crack propagation was so complicated that further systematic investigations are necessary in future in connection with the effects of particles on the formation of substructure in the plastic zone.