The role of deformed rail microstructure on rolling contact fatigue initiation

Wear ◽  
2008 ◽  
Vol 265 (9-10) ◽  
pp. 1363-1372 ◽  
Author(s):  
John E. Garnham ◽  
Claire L. Davis
Keyword(s):  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Fatigue Initiation

A New Methodology to Evaluate the Rolling Contact Fatigue Performances of Bearing Steels With Surface Dents: Application to 32CrMoV13 (Nitrided) and M50 Steels

2003 ◽  
Author(s):  
D. Ne´lias ◽  
C. Jacq ◽  
G. Lormand ◽  
G. Dudragne ◽  
A. Vincent
Keyword(s):  
Test Specimen ◽  
Normal Load ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Experimental Procedure ◽  
Bearing Steels ◽  
Indentation Process ◽  
Hoop Stresses

A new methodology is proposed to evaluate the rolling contact fatigue (RCF) performances of bearing steels in presence of surface dents. The experimental procedure consists in denting the raceway of the test specimen with a hardness machine using spherical diamond tips of different radius, i.e. 200, 400 and 600 μm, and normal loads ranging from 5 to 50 daN. Analysis of various dent geometries yields to an analytical law with five parameters useful to fit experimental profiles for contact simulation. Besides local residual stresses and plastic strains around the dent have been obtained by finite element simulations of the indentation process. RCF tests performed on a two-disk machine have shown better performances of nitrided 32CrMoV13 steel compared to M50 reference steel. The dominating role of sliding has been highlighted and two areas where damage initiates were identified, while the effects of the normal load and hoop stresses are less marked.

Location of an acoustic emission source in a radially loaded deep groove ball-bearing

1998 ◽  
Vol 212 (1) ◽  
pp. 33-45 ◽  
Author(s):  
D Nélias ◽  
T Yoshioka
Keyword(s):  
Acoustic Emission ◽  
Ball Bearing ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Bearing ◽  
Rolling Contact ◽  
Fatigue Initiation ◽  
Deep Groove ◽  
Deep Groove Ball Bearing ◽  
Subsurface Defect

This paper describes a deep groove ball-bearing analysis which has been developed to simulate acoustic emission occurring during ball-bearing operation. The computer simulation is useful to clarify experimental research on rolling contact fatigue initiation using the acoustic emission technique. Results show the ability of the method to detect and to locate a subsurface defect, due to rolling contact fatigue, before the rolling bearing failure occurs. The subsurface defect can be accurately located within the inner ring of a deep groove ball-bearing operating under radial load.

scholarly journals The Role of Elastohydrodynamic Lubrication in Rolling-Contact Fatigue

1963 ◽  
Vol 85 (3) ◽  
pp. 439-447 ◽  
Author(s):  
E. V. Zaretsky ◽  
L. B. Sibley ◽  
W. J. Anderson
Keyword(s):  
Fatigue Life ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Elastohydrodynamic Lubrication ◽  
Rolling Contact ◽  
Contact Fatigue Life ◽  
Steel Balls ◽  
Thickness Measurements ◽  
Ball Test

The five-ball fatigue tester was used to determine the rolling-contact fatigue life of 1/2-inch-diameter M-1 steel balls with four lubricants at 300 deg F. Film thickness measurements were made with the rolling-contact disk machine under simulated five-ball test conditions. Under certain conditions, elastohydrodynamic lubrication was found to exist at initial maximum Hertz stress levels up to 800,000 psi. There appears to be a correlation among the following variables: Plastically deformed profile radius of the ball specimen at ambient temperature; lubricant type; and rolling-contact fatigue. No correlation was found between contact temperature obtained with different lubricants and fatigue life.

Experimental and Theoretical Investigation on Rolling Contact Fatigue of 52100 and M50 Steels Under EHL or Micro-EHL Conditions

1998 ◽  
Vol 120 (2) ◽  
pp. 184-190 ◽  
Author(s):  
D. Ne´lias ◽  
M.-L. Dumont ◽  
F. Couhier ◽  
G. Dudragne ◽  
L. Flamand
Keyword(s):  
Rolling Contact Fatigue ◽  
Large Population ◽  
Contact Fatigue ◽  
Surface Damage ◽  
Rolling Contact ◽  
Surface Finishing ◽  
Micro Cracks ◽  
Pure Rolling ◽  
Surface Distress

The purpose of this investigation is to clarify the role of roughness on rolling contact fatigue. Tests have been carried out on a two-disk machine, for two rolling bearing steels (52100 and M50), two surface roughnesses corresponding to EHL and micro-EHL conditions (two different surface finishing), three normal loadings (1.5, 2.5 and 3.5 GPa), and under pure rolling or rolling plus sliding conditions. No surface damage has been observed up to 50 106 cycles for tests with smooth specimens. Tests with rough specimens have produced a typical surface damage, called here surface distress, made of a large population of asperity-scale micro-cracks and micro-spalls. The paper describes the surface distress observed, such as micro-cracks and micro-spalls. Surface damages obtained are different for tests under pure rolling conditions and tests under rolling plus sliding conditions. Therefore, the role of the friction direction is underlined. A link is made between our experimental observations and calculations that have been carried out using a transient EHL model. The influence of an indent in a line contact, simulating a micro-spall, is studied. Surface pressure and associated sub-surface stress field are analyzed versus the sliding direction.

Sign in / Sign up

Export Citation Format

Share Document