FATIGUE POINT DEPENDENCE OF NOTCHED SPECIMENTS UPON THE THICKNESS OF HARDENED SURFACE LAYER
The undertaken research has shown that the advance of surface plastic deformation increase in layer thickness with compressive residual stress smooth specimens leads to increased fatigue strength in notched specimens at the expense of increasing the compressive residual stresses in their dangerous section. With the increase in the diameter of the samples at the same hardening surface treatment of layer thickness with compressive residual stress is increased by increasing the hardness of the samples. Evaluation increment of fatigue point of surface hardened cylindrical samples with circular incisions semicircular profile gives acceptable results in practice that will significantly reduce the lengthy and costly fatigue tests.