β Scribed by D. H. Banasiak; A. F. Grandt Jr.; L. T. Montulli
No coin nor oath required. For personal study only.
Results are presented from a recent study of the influence of tensile overloads on fatigue crack growth in polycarbonate. Fatigue cracks were grown under conditions of constant range in stress intensity factor in fourβpoint bend specimens. The data presented here indicate that tensile overloads may significantly retard subsequent fatigue crack growth in polycarbonate. The period of delay in crack growth was shown to increase with the magnitude of the overload. Recovery of stable crack extension following the overload appeared to involve reinitiation of separate crack growth sites at the tip of the blunted crack tip, similar to the original crack initiation at sharp Vβnotches.
π SIMILAR VOLUMES
Abstraet-The presented results are from an investigation of crack surface profiles and the influence of intermittent overloads on fatigue crack growth in polymethylmethacrylate, a transparent polymer. Fatigue cracks were grown in compact tension specimens under conditions of constant range in stress
Abstract4onstant amplitude and spectrum loading fatigue crack growth rate tests were performed on HP-9Ni4X+3OC steel heat treated to three strength levels. It was concluded that the constant nmplltude crack growth rate is dependent on the stxenath level of the material and independent of the toughne