Fatigue life prediction of components made of spheroidal graphite cast iron

摘要

In many cast metals fatigue crack initiates from a defect. The lower bound of the fatigue life in cast components can be estimated based on the maximum defect size which is present in a component. In this research the distribution of defects in a ferritic spheroidal graphite cast iron component was determined. Then, Gumbel distribution was used to estimate the maximum sizes of defects in cylindrical fatigue specimens with different dimensions. Based on estimated maximum defect size, the fracture mechanics approach was used to determine the lower bound of the fatigue life for fatigue specimens with different dimensions and the geometrical size effect was modeled.