wear and surface fatigue in rolling bearings evolution

Strictly speaking the above described surface contact fatigue process is defined as the evolution of damage that occurs when two specific moving surfaces touch each other repeatedly allied to other processes such as corrosion pit formation wear debris and fatigue cracks The damage process may reduce the component's load-bearing capacity Rolling bearing operation is affected by friction wear and lubrication mechanisms fluid dynamics and lubricant rheology material properties and contact mechanics Changes in rolling surfaces occur due to plastic deformation rolling contact wear and rolling contact fatigue Wear particles can be formed and mixed into the lubricant

Stress Field Evolution in a Ball Bearing Raceway Fatigue Spall

failure 4 These surface fatigue failures occur in the form of surface pitting or spalls on a ball or raceway surface This type of surface fatigue failure is also observed in gears cam-followers and rails 5 6 Conventional bearing fatigue life is usually defined as the amount of time or number of load cycles needed to initiate a surface

Rolling contact fatigue (RCF) is responsible for the fail-ure of rolling element bearings gears camshafts and may be defined as cracking or pitting/delamination limited to the near-surface layer of bodies in rolling/sliding contact There is an increased demand for improved life reliability and load bearing capacity of bearing materials and

Often rolling contact fatigue damage originated around surface microgeometry features develops into a spall Spall propagation in its advanced form is strongly influenced by macrogeometry aspects – for example the evolution of the raceway contact geometry and resulting overall stress field in a rolling bearing

failure 4 These surface fatigue failures occur in the form of surface pitting or spalls on a ball or raceway surface This type of surface fatigue failure is also observed in gears cam-followers and rails 5 6 Conventional bearing fatigue life is usually defined as the amount of time or number of load cycles needed to initiate a surface

of the rolling contact fatigue (RCF) [1–5] This kind of damage is the dominant form of failure for rolling bearings The fatigue life of bearings depends on many factors and variables such as the size and direction of the loadings the geometry and roughness of the contact surfaces the kind of

QIBR Bearing Damage Analysis with Lubrication Reference

Abrasive Wear Fine foreign material in the bearing can cause excessive abrasive wear Sand fine metal from grinding or machining and fine metal or carbides from gears wear or lap the rolling elements and races In tapered bearings the roller ends and cone rib wear to a greater degree than the races This wear causes increased endplay or internal

In this article an engineering approach is described to model micropitting in rolling–sliding heavily loaded lubricated contacts The competitive mechanism between surface fatigue and mild wear is captured in the present approach as well as the effects of deterministic surface

SURFACE FATIGUE Surface fatigue is the failure of a material as a result of repeated surface or sub-surface stresses beyond the endurance limit of the material Figure 2 1 indicates the theoretical mutual Hertzian stresses occurring when a gear and pinion mesh There are compressive stresses at the surface and unidirectional and bi-directional

An experimental and theoretical study of surface rolling contact fatigue damage progression in hybrid bearings with artificial dents C Vieillarda n Y Kadina G E Morales-Espejela b A Gabellia a QIBR Engineering Research Centre Nieuwegein The Netherlands b Universit de Lyon CNRS LaMCoS UMR 5259 F69621 Lyon France article info

The effect of machining conditions on the rolling contact fatigue (RCF) strength of PEEK polymer bearings was investigated RCF tests were carried out by using bearings machined by different conditions The surface profile and roughness were observed before and after testing by laser confocal microscope Pitting and cracking were associated with the different initial surface conditions

Fatigue wear is a type of wear where a number of cycles is needed to generate debris The fatigue process in metals may induce the generation of surface and subsurface cracks which after a critical number of cycles results in a severe damage such as large fragments leaving the surface[1 2]

Modelling the interaction wear-fatigue To model the interaction wear/fatigue in bearings a rolling contact fatigue (RCF) model needs to be applied at every over-rolling of the raceway with a previously modified profile (on both surfaces) due to wear in this way both phenomena (wear and fatigue) interact

An experimental and theoretical study of surface rolling contact fatigue damage progression in hybrid bearings with artificial dents C Vieillarda n Y Kadina G E Morales-Espejela b A Gabellia a QIBR Engineering Research Centre Nieuwegein The Netherlands b Universit de Lyon CNRS LaMCoS UMR 5259 F69621 Lyon France article info

The Evolution of White Etching Cracks (WECs) in Rolling

The formation of white etching cracks (WECs) in steel rolling element bearings can lead to the premature rolling contact fatigue (RCF) failure mode called white structure flaking (WSF) Driving mechanisms are still debated but are proposed to be combinations of mechanical tribochemical and electrical effects

failure 4 These surface fatigue failures occur in the form of surface pitting or spalls on a ball or raceway surface This type of surface fatigue failure is also observed in gears cam-followers and rails 5 6 Conventional bearing fatigue life is usually defined as the amount of time or number of load cycles needed to initiate a surface

of the rolling contact fatigue (RCF) [1–5] This kind of damage is the dominant form of failure for rolling bearings The fatigue life of bearings depends on many factors and variables such as the size and direction of the loadings the geometry and roughness of the contact surfaces the kind of

Even when operating correctly rolling element bearings will eventually fail as a result of a surface fatigue phenomenon Rolling element bearing surface fatigue is characterized by spalling It starts after some variable time of service as embryonic particles that are liberated from the surface of a race or rolling element in the load zone

May 01 2005Abstract A review of some of the recent work on the mechanism of rolling contact fatigue (RCF) is presented Topics covered include the appearance and classification of RCF and the processes of strain localization texture development microstructural change crack formation crack shape and propagation and through-fracture

A combined experimental and numerical methodology is developed for the investigation of progressive evolution of subsurface plasticity during prolonged rolling contact fatigue (RCF) loading of a M50 NiL case hardened steel Three balls-on-rod RCF tests have been performed on a M50 NiL steel rod a using silicon nitride balls over several hundred million cycles at 5 5 GPa contact stress level

Strictly speaking the above described surface contact fatigue process is defined as the evolution of damage that occurs when two specific moving surfaces touch each other repeatedly allied to other processes such as corrosion pit formation wear debris and fatigue cracks The damage process may reduce the component's load-bearing capacity

Rolling-sliding wear experiments were performed to investigate the wear and rolling contact fatigue (RCF) behaviours of a premium pearlitic rail (PH) a carbon-free bainitic rail (BH) and two standard pearlitic rails (U71Mn and U75V) The surface hardness evolution of rail discs before and after experiments is shown in Fig 7 The rail