Analytical Results of Fatigue Reliability for Structural Steels Based on “Database on Fatigue Strength of Metallic Materials”

Abstract

The fatigue properties of the structural steels were investigated based on “Database on Fatigue Strength of Metallic Materials” published by the Society of Material Science, Japan. The rotating bending fatigue test results for pure iron and structural steels JIS S10C-S58C were extracted from the database and hyperbola regression model was applied based on the JSMS standard, “Standard Evaluation Method of Fatigue Reliability for Metallic Materials-Standard Regression Method of S-N Curve-”. The correlations between obtained regression parameters were investigated and it is revealed that there were strong correlation between (1) tensile strength σB and fatigue limit E, (2) slope A and intercept B of inclined part of S-N curve, (3) slope A and the critical number of stress cycles giving fatigue limit Nw. In addition, a number of fatigue data extracted were normalized by tensile strength of σB and pooled altogether. Using these data sets, the P-S-N property was also analyzed and it is confirmed that the fatigue life distribution shows complex pattern and changes at each stress level for evaluation, while fatigue strength distribution shows relatively simple pattern and were approximately identical at different number of cycles.