1. School of PetroChemical Engineering, Lanzhou University of Techno-logy, Lanzhou 730050, China 2. School of Mechanical Engineering and Mechanics, Ningbo University, Ningbo 315211, China
Wind turbine gearbox bearings fail with the service life is much shorter than the designed life. Gearbox bearings are subjected to rolling contact fatigue (RCF) and they are observed to fail due to axial cracking, surface flaking, and the formation of white etching areas (WEAs). The current study reviewed these three typical failure modes. The underlying dominant mechanisms were discussed with emphasis on the formation mechanism of WEAs. Although numerous studies have been carried out, the formation of WEAs remains unclear. The prevailing mechanism of the rubbing of crack faces that generates WEAs was questioned by the authors. WEAs were compared with adiabatic shear bands (ASBs) generated in the high strain rate deformation in terms of microstructural compositions, grain refinement, and formation mechanism. Results indicate that a number of similarities exist between them. However, substantial evidence is required to verify whether or not WEAs and ASBs are the same matters.
M Whittle, J Trevelyan, P J Tavner. Bearing currents in wind turbine generators. Journal of Renewable and Sustainable Energy, 2013, 5(5): 053128 https://doi.org/10.1063/1.4822048
2
M H Evans. White structure flaking (WSF) in wind turbine gearbox bearings: Effects of ‘butterflies’ and white etching cracks (WECs). Materials Science and Technology, 2012, 28(1): 3–22 https://doi.org/10.1179/026708311X13135950699254
3
P E Morthorst, S Awerbuch. The Economics of Wind Energy: A report by the European Wind Energy Association. 2009.
4
M H Evans, J C Walker, C Ma, et al.A FIB/TEM study of butterfly crack formation and white etching area (WEA) microstructural changes under rolling contact fatigue in 100Cr6 bearing steel. Materials Science and Engineering: A, 2013, 570: 127–134 https://doi.org/10.1016/j.msea.2013.02.004
5
A Grabulov, R Petrov, H W Zandbergen. EBSD investigation of the crack initiation and TEM/FIB analyses of the microstructural changes around the cracks formed under rolling contact fatigue (RCF). International Journal of Fatigue, 2010, 32(3): 576–583 https://doi.org/10.1016/j.ijfatigue.2009.07.002
6
M H Evans, A D Richardson, L Wang, et al.Serial sectioning investigation of butterfly and white etching crack (WEC) formation in wind turbine gearbox bearings. Wear, 2013, 302(1–2): 1573–1582 https://doi.org/10.1016/j.wear.2012.12.031
7
A Grabulov, U Ziese, H W Zandbergen. TEM/SEM investigation of microstructural changes within the white etching area under rolling contact fatigue and 3-D crack reconstruction by focused ion beam. Scripta Materialia, 2007, 57(7): 635–638 https://doi.org/10.1016/j.scriptamat.2007.06.024
8
K Hashimoto, K Hiraoka, K Kida, et al.Effect of sulphide inclusions on rolling contact fatigue life of bearing steels. Materials Science and Technology, 2012, 28(1): 39–43 https://doi.org/10.1179/1743284711Y.0000000062
9
R Errichello, R Budny, R Eckert. Investigations of bearing failures associated with white etching areas (WEAs) in wind turbine gearboxes. Tribology Transactions, 2013, 56(6): 1069–1076 https://doi.org/10.1080/10402004.2013.823531
10
M H Evans. An updated review: White etching cracks (WECs) and axial cracks in wind turbine gearbox bearings. Materials Science and Technology, 2016, 32(11): 1133–1169 https://doi.org/10.1080/02670836.2015.1133022
11
S Janakiraman, O West, P Klit, et al.Observations of the effect of varying hoop stress on fatigue failure and the formation of white etching areas in hydrogen infused 100Cr6 steel rings. International Journal of Fatigue, 2015, 77: 128–140 https://doi.org/10.1016/j.ijfatigue.2015.03.011
12
J Luyckx. White etching crack failure mode in roller bearings: From observation via analysis to understanding and an industrial solution. Rolling Element Bearings, 2012, 1542: 1–25
T Sakai, B Lian, M Takeda, et al.Statistical duplex S-N, characteristics of high carbon chromium bearing steel in rotating bending in very high cycle regime. International Journal of Fatigue, 2010, 32(3): 497–504 https://doi.org/10.1016/j.ijfatigue.2009.08.001
15
A Ruellan, F Ville, X Kleber. Understanding white etching cracks in rolling element bearings: The effect of hydrogen charging on the formation mechanisms. Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology, 2014, 228(11): 1252–1265
16
Y Li, G Kang, C Wang, et al.Vertical short-crack behavior and its application in rolling contact fatigue. International Journal of Fatigue, 2006, 28(7): 804–811 https://doi.org/10.1016/j.ijfatigue.2005.06.047
17
G Donzella, C Petrogalli. A failure assessment diagram for components subjected to rolling contact loading. International Journal of Fatigue, 2010, 32(2): 256–268 https://doi.org/10.1016/j.ijfatigue.2009.06.016
18
S V Kailas. A study of the strain rate microstructural response and wear of metals. Journal of Materials Engineering and Performance, 2003, 12(6): 629–637 https://doi.org/10.1361/105994903322692411
19
J W Seo, H K Jun, S J Kwon, et al.Rolling contact fatigue and wear of two different rail steels under rolling-sliding contact. International Journal of Fatigue, 2016, 83: 184–194 https://doi.org/10.1016/j.ijfatigue.2015.10.012
B Gould, A Greco. The influence of sliding and contact severity on the generation of white etching cracks. Tribology Letters, 2015, 60(2): 29 https://doi.org/10.1007/s11249-015-0602-6
22
D Nélias, M L Dumont, F Champiot, et al.Role of inclusions, surface roughness and operating conditions on rolling contact fatigue. Journal of Tribology, 1999, 121(2): 240–250 https://doi.org/10.1115/1.2833927
23
W Solano-Alvarez, E J Pickering, M J Peet, et al.Soft novel form of white-etching matter and ductile failure of carbide-free bainitic steels under rolling contact stresses. Acta Materialia, 2016, 121: 215–226 https://doi.org/10.1016/j.actamat.2016.09.012
24
J H Kang, B Hosseinkhani, P E J Rivera-díaz-del-castillo. Rolling contact fatigue in bearings: Multiscale overview. Materials Science and Technology, 2012, 28(1): 44–49 https://doi.org/10.1179/174328413X13758854832157
25
H Harada, T Mikami, M Shibata, et al.Microstructural changes and crack initiation with white etching area formation under rolling/sliding contact in bearing steel. ISIJ International, 2005, 45(12): 1897–1902 https://doi.org/10.2355/isijinternational.45.1897
26
G Baumann, K Knothe, H J Fecht. Surface modification, corrugation and nanostructure formation of high speed railway tracks. Nanostructured Materials, 1997, 9(1–8): 751–754 https://doi.org/10.1016/S0965-9773(97)00162-1
27
X Qin, D Sun, L Xie, et al.Hardening mechanism of Cr5 backup roll material induced by rolling contact fatigue. Materials Science and Engineering: A, 2014, 600: 195–199 https://doi.org/10.1016/j.msea.2014.01.100
28
M H Evans, A D Richardson, L Wang, et al.Confirming subsurface initiation at non-metallic inclusions as one mechanism for white etching crack (WEC) formation. Tribology International, 2014, 75: 87–97 https://doi.org/10.1016/j.triboint.2014.03.012
29
Y Imai, T Endo, D Dong, et al.Study on rolling contact fatigue in hydrogen environment at a contact pressure below basic static load capacity. Tribology Transactions, 2010, 53(5): 764–770 https://doi.org/10.1080/10402001003790186
30
H Uyama, H Yamada, H Hidaka, et al.The effects of hydrogen on microstructural change and surface originated flaking in rolling contact fatigue. Tribology Online, 2011, 6(2): 123–132 https://doi.org/10.2474/trol.6.123
31
T Bruce, E Rounding, H Long, et al.Characterisation of white etching crack damage in wind turbine gear-box bearings. Wear, 2015, 338–339: 164–177 https://doi.org/10.1016/j.wear.2015.06.008
R H Vegter, J T Slycke, J Beswick, et al. The role of hydrogen on rolling contact fatigue response of rolling element bearings. Journal of ASTM International, 2010, 7(2): 102543
34
K Hiraoka, T Fujimatsu, N Tsunekage, et al. Generation process observation of microstructural change in rolling contact fatigue by hydrogen-charged specimens. Japanese Journal of Tribology, 2007, 52(6): 673–683
H Hamada, Y Matsubara. The influence of hydrogen on tension-compression and rolling contact fatigue properties in bearing steel. NTN Technical Review, 2006, 74: 54–61
37
M H Evans, A D Richardson, L Wang, et al.Effect of hydrogen on butterfly and white etching crack (WEC) formation under rolling contact fatigue (RCF). Wear, 2013, 306(1–2): 226–241 https://doi.org/10.1016/j.wear.2013.03.008
38
J H Kang, R H Vegter, P E J Rivera-Díaz-del-Castillo. Rolling contact fatigue in martensitic 100Cr6: Subsurface hardening and crack formation. Materials Science and Engineering: A, 2014, 607: 328–333 https://doi.org/10.1016/j.msea.2014.03.143
39
J H Kang, B Hosseinkhani, C A Williams, et al.Solute redistribution in the nanocrystalline structure formed in bearing steels. Scripta Materialia, 2013, 69(8): 630–633 https://doi.org/10.1016/j.scriptamat.2013.07.017
40
S Li, Y Su, X Shu, et al.Microstructural evolution in bearing steel under rolling contact fatigue. Wear, 2017, 380–381: 146–153 https://doi.org/10.1016/j.wear.2017.03.018
41
J Lai, K Stadler. Investigation on the mechanisms of white etching crack (WEC) formation in rolling contact fatigue and identification of a root cause for bearing premature failure. Wear, 2016, 364–365: 244–256 https://doi.org/10.1016/j.wear.2016.08.001
42
K Hiraoka, M Nagao, T Isomoto. Study on flaking process in bearings by white etching area generation. Journal of ASTM International, 2006, 3(5): 14059 https://doi.org/10.1520/JAI14059
43
W Solano-Alvarez, J Duff, M C Smith, et al.Elucidating white-etching matter through high-strain rate tensile testing. Materials Science and Technology, 2017, 33(3): 307–310 https://doi.org/10.1080/02670836.2016.1195981
44
A Warhadpande, F Sadeghi, R D Evans. Microstructural alterations in bearing steels under rolling contact fatigue Part 1—Historical overview. Tribology Transactions, 2013, 56(3): 349–358 https://doi.org/10.1080/10402004.2012.754073
45
B Gould, A Greco. Investigating the process of white etching crack initiation in bearing steel. Tribology Letters, 2016, 62(2): 26 https://doi.org/10.1007/s11249-016-0673-z
46
Q Wei, L Kecskes, T Jiao, et al.Adiabatic shear banding in ultrafine-grained Fe processed by severe plastic deformation. Acta Materialia, 2004, 52(7): 1859–1869 https://doi.org/10.1016/j.actamat.2003.12.025
47
N Li, Y D Wang, R Lin Peng, et al.Localized amorphism after high-strain-rate deformation in TWIP steel. Acta Materialia, 2011, 59(16): 6369–6377 https://doi.org/10.1016/j.actamat.2011.06.048
48
S Li, P Zhao, Y He, et al.Microstructural evolution associated with shear location of AISI 52100 under high strain rate loading. Materials Science and Engineering: A, 2016, 662: 46–53 https://doi.org/10.1016/j.msea.2016.03.050
49
B F Wang, Y Yang. Microstructure evolution in adiabatic shear band in fine-grain-sized Ti-3Al-5Mo-4.5V alloy. Materials Science and Engineering: A, 2008, 473(1–2): 306–311 https://doi.org/10.1016/j.msea.2007.03.073
50
J Peirs, W Tirry, B Amin-Ahmadi, et al.Microstructure of adiabatic shear bands in Ti6Al4V. Materials Characterization, 2013, 75: 79–92 https://doi.org/10.1016/j.matchar.2012.10.009
51
A P Voskamp. Material response to rolling contact loading. Journal of Tribology, 1985, 107(3): 359–364 https://doi.org/10.1115/1.3261078
