Fatigue strength study based on geometric shape of bulk defects in cast steel

This work applies Taylor's Theory of Critical Distances (TCD) to assess the fatigue strength of defect-afflicted cast steel components made of G21Mn5+N. Based on radiographs of complexly shaped spatial imperfections, the established TCD-framework leads to a sound agreement of numerical and experimental fatigue strength. Moreover, a novel fatigue assessment methodology is presented, which bases on the projected planar defect shape, featuring an engineering-feasible design method without the need of extensive numerical simulations. About one-hundred additional imperfections referring to ASTM E446 class A and C validate the model, showing an average deviation of about five percent in fatigue strength.

Automated summary

This study applies Taylor's Theory of Critical Distances to assess the fatigue strength of defect-afflicted cast steel components and presents a new methodology for fatigue assessment based on the projected planar defect shape. The results show good agreement with experimental data and the method does not require extensive numerical simulations.