抄録
A series of experiments are conducted to investigate the impact fatigue crack growth behavior of O.1%C aluminum killed carbon steel conforming to JIS. S10C. And results obtained are discussed from several viewpoints in comparison with those in non impact fatigue. It is clear that macroscopic crack growth rate, da/dN, in impact fatigue is higher than that in non impact fatigue especially in relatively low Kmax or low ΔK region. Through quantitative analysis of fracture surface morphology, it is revealed that the higher crack growth rate in impact fatigue is sustained by the larger amount of intergranular fracture mode which accelarates crack growth rate to some extent. Other characteristical aspects in impact fatigue crack growth behavior are also described in detail.
