Effect of non-metallic inclusions on AISI 4140 fatigue strength

• A fatigue strength assessment procedure for steels with inclusions is proposed. Such a implements defect content analysis and the area -parameter model. The multiaxial critical plane-based criterion by Carpinteri at al. also implemented. return period optimisation , in terms of estimations, performed. An experimental campaign analysed to evaluate accuracy above procedure. In present paper, high steel (AISI 4140) containing non-metallic (NMIs) implements: (i) analysis, (ii) model, (iii) According distribution NMIs determined two cross-sections perpendicular maximum principal stress directions under normal shear uniaxial cyclic loadings. periods, obtained optimising estimation, are taking into account five different prediction volumes. results achieved through proposed compared both data employing et without optimisation.