Hydrogen Degradation of Material of a Bearing Ring Fitted on a Rotating Shaft

The article is devoted to the problem of bearing steel weakening under the negative influence of hydrogen released as a result of the decay of the lubricant during friction. Hydrogen changes the mechanical properties of the metal, affecting the stress-strain state of the shaft and bearing ring, which, in turn, affects the distribution of hydrogen in the system. In this work the stress-strain state of the rotating shaft and the inner ring of the bearing installed with an interference fit is determined. The dependences of mechanical stresses on the radial coordinate are constructed for various values of preliminary interference fit and angular velocity of rotation. The dependences of the diffusion coefficient and hydrogen concentration on the radial coordinate in a stressed shaft-ring system are obtained. It is shown that under the influence of stresses and free hydrogen in the bearing ring, conditions for the degradation of the material are created. The accepted hypothesis about the condition of hydrogen atoms wedging into the crystal lattice of the metal made it possible to carry out a preliminary assessment of the effect of hydrogen on the elastic modulus of the bearing ring material.