Experimental investigations were carried out to better understand the rolling contact fatigue mechanisms in nitrided layers of the 33CrMoV12-9 steel grade. Surface-initiated pitting failure mode was reproduced on a twin-disc machine to analyse crack growth and compressive residual stress behaviour within the nitrided layers. Metallographic examinations, 3D observations by means of high-resolution X-ray computed tomography and residual stress analysis were realised on nitrided 33CrMoV12-9 specimens before and after rolling contact fatigue tests. The study revealed that if the initial compressive residual stresses associated with the surface treatment are released during the process of rolling contact fatigue, pre-existing superficial cracks propagate in the nitrided layers along the intergranular carbides. These precipitates induced by the nitriding process therefore act as preferential crack propagation sites.
SureshS. Fatigue of materials▪▪. Cambridge solid state science series. Cambridge: Cambridge University Press, 1998.
2.
JohnsonKL. Contact mechanics, Cambridge: Cambridge University Press, 1987.
3.
KanetaMSuetsuguMMurakamiY. Mechanism of surface crack-growth in lubricated rolling sliding spherical contact. J Appl Mech1986; 53: 354–360.
4.
MeheuxMMinfrayCVilleFet al.Effect of lubricant additives in rolling contact fatigue. Proc IMechE, Part J: J Engineering Tribology2010; 224: 947–955.
5.
RuellanAVilleFKleberXet al.Understanding white etching cracks in rolling element bearings: The effect of hydrogen charging on the formation mechanisms. Proc IMechE, Part J: J Engineering Tribology2014; 228: 1252–1265.
6.
VoskampAP. Material response to rolling contact loading. J Tribol1985; 107: 359–364.
7.
SchlichtHSchreiberOZwirleinE. Effects of material properties on bearing steel fatigue strength. In: Effect of steel manufacturing processes on the quality of bearing steels, West Conshohocken, PA: ASTM International, 1988.
8.
Olver AV, Cole SJ and Sayles RS. Contact stresses in nitrided steels. In: Proceedings of 19th Leeds-Lyon symposium on tribology, Leeds, 1993.
9.
WilkinsonCMROlverAV. The durability of gear and disc specimens - part i: The effect of some novel materials and surface treatments. Tribol Trans1999; 42: 503–510.
10.
BarrallierLTraskineVBotchenkovS. Morphology of intergranular cementite arrays in nitrided chromium-alloyed steels. Mater Sci Eng A2005; 393: 247–253.
11.
LeMVilleFKleberXet al.Influence of grain boundary cementite induced by gas nitriding on the rolling contact fatigue of alloyed steels for gears. Proc IMechE, Part J: J Engineering Tribology2015.
12.
VilleFNéliasDTourloniasGet al.On the two-disc machine: A polyvalent and powerful tool to study fundamental and industrial problems related to elastohydrodynamic lubrication. Tribology series2001; vol. 39, New York: Elsevier, pp. 393–402.
13.
Diab Y, Coulon S, Ville F, et al. Experimental investigations on rolling contact fatigue of dented surfaces using artifical, defects: Subsurface analyses. In: Dalmaz G, Dowson D, Priest M, Lubrecht AA (eds) In: Tribological research and design for engineering systems proceedings of the 29th Leeds-Lyon symposium on tribology, Vol. 41 of Tribology Series, 2003, pp.359–366. New York: Elsevier.
14.
CoulonSJubaultILubrechtAAet al.Pressure profiles measured within lubricated contacts in presence of dented surfaces. comparison with numerical models. Tribol Int2002; 37: 111–117.
15.
VilleFCoulonSLubrechtAA. Influence of solid contaminants on the fatigue life of lubricated machine elements. Proc IMechE, Part J: J Engineering Tribology2006; 220: 441–445.
16.
LabiauAVilleFSainsotPet al.Effect of sinusoidal surface roughness under starved conditions on rolling contact fatigue. J Eng Tribol2008; 222: 193–200.
17.
FabreAEvansHPBarrallierLet al.Prediction of microgeometrical influences on micropitting fatigue damage on 32crmov13 steel. Tribol Int2013; 59: 129–140.
18.
MartinsRLocatelliCSeabraJ. Evolution of tooth flank roughness during gear micropitting tests. Ind Lubric Tribol2011; 63: 34–45.
19.
KanetaMYatsuzukaHMurakamiY. Mechanism of crack growth in lubricated rolling/sliding contact. ASLE Trans1985; 28: 407–414.
20.
BuffièreJ-YProudhonHFerrieEet al.Three dimensional imaging of damage in structural materials using high resolution micro-tomography. Nucl Instrum Methods Phys Res B2005; 238: 75–82.
21.
ISO 6336-5. Calculation of load capacity of spur and helical gears - Part 5: Strength and quality of materials2003.
22.
Jegou S. Influence des éléments d’alliage sur la genèse des contraintes résiduelles d’aciers nitrurés. PhD Thesis, Arts et Métiers ParisTech, France, 2009.
23.
MuroHTsushimaN. Microstructural, microhardness and residual stress changes due to rolling contact. Wear1970; 15: 309–330.
24.
VoskampAP. Fatigue and material response in rolling contact, New York: American Society for Testing and Materials, 1998.
25.
SadeghiFJalalahmadiBSlackTSet al.A review of rolling contact fatigue. J Tribol2009. 131/041403: 1–15.
26.
BhadeshiaHKDH. Steels for bearings. Prog Mater Sci2012; 57: 268–435.
