Effect of surface stress concentrators and microstructure on the fatigue limit of the material

Abstract

A calculation model is developed that makes it possible to predict the fatigue limit s -1 of specimens with technological surface defects based on the data on the material microstructure and stress concentrator geometry. The fatigue test results are presented for specimens with technological defects under symmetric lateral bending that are made of Ti-6Al-4V titanium alloy condensate produced by the electron-beam physical vapor deposition method. The results obtained are used to calculate s -1 based on the developed model and are in very good agreement with the experimental data.

Fracture Assessment of Blunt V-Notched Graphite Specimens by Means of the Strain Energy Density

“…The stress raisers concentrate stresses around themselves and make a hazardous region with high risk of initiating crack(s) and provoking sudden fracture. Therefore, the fracture resistance of graphite parts should be essentially investigated under mechanical loads, particularly in the presence of stress concentrators [1][2][3][4][5] or sharp cracks [6][7][8].…”