Multiaxial Stress State and Neubers Rule

6 Strain-Based Fatigue Analysis Low Cycle Fatigue 

Equation (6.42) indicates, for example, that with a root radius of 0.5 mm the corresponding TF is 1.83. Entering the curve of Fig. 6.25 with this value it yields a ductility loss of about 90 %. A rather big warning mark must be introduced at this time since this actually means that a material that imder uniaxial traction fails at a deformation of 35 % under plain strain condition will not reach more than 3.5 % strain. 

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