The aim of this paper is to assess the very-high-cycle fatigue (VHCF) behaviour of a magnesium alloy (ZK60). Results indicate that the fatigue crack initiates from an area consisting of many distributed facets, while the region of early crack propagation is characterised by parallel traces, based on a fractographic analysis. The significant differences in morphology around the crack initiation area result from the interaction between the deformation twinning and the plastic zone at the crack tip. In addition, the fatigue crack propagation rate around the crack initiation site is also estimated based on a modified Murakami model. It is found that the formation stage for the fatigue crack is of great importance to the fatigue failure mechanism in the VHCF regime.
WangQY, BerardJY, DubarreA, Gigacycle fatigue of ferrous alloys. Fatigue Fract Eng M. 1999;22:667–672. doi: 10.1046/j.1460-2695.1999.t01-1-00185.x
2.
BathiasC, ParisPC.Gigacycle fatigue of metallic aircraft components. Int J Fatigue. 2010;32:894–897. doi: 10.1016/j.ijfatigue.2009.03.015
3.
Stanzl-TscheggS, MughrabiH, SchoenbauerB.Life time and cyclic slip of copper in the VHCF regime. Int J Fatigue. 2007;29:2050–2059. doi: 10.1016/j.ijfatigue.2007.03.010
4.
WangQ, Palin-LucT.Guest editorial for VHCF6 special topic. Fatigue Fract Eng M. 2015;38:1265–1265. doi: 10.1111/ffe.12350
5.
HongYS, LeiZQ, SunCQ, Propensities of crack interior initiation and early growth for very-high-cycle fatigue of high strength steels. Int J Fatigue. 2014;58:144–151. doi: 10.1016/j.ijfatigue.2013.02.023
6.
MughrabiH.Specific features and mechanisms of fatigue in the ultrahigh-cycle regime. Int J Fatigue. 2006;28:1501–1508. doi: 10.1016/j.ijfatigue.2005.05.018
7.
SpriestersbachD, GradP, KerscherE.Influence of different non-metallic inclusion types on the crack initiation in high-strength steels in the VHCF regime. Int J Fatigue. 2014;64:114–120. doi: 10.1016/j.ijfatigue.2014.03.003
8.
ZhaoA, XieJ, SunC, Prediction of threshold value for FGA formation. Mater Sci Eng A. 2011;528:6872–6877. doi: 10.1016/j.msea.2011.05.070
9.
LiYD, ZhangLL, FeiYH, On the formation mechanisms of fine granular area (FGA) on the fracture surface for high strength steels in the VHCF regime. Int J Fatigue. 2016;82:402–410. doi: 10.1016/j.ijfatigue.2015.08.021
10.
GradP, ReuscherB, BrodyanskiA, Mechanism of fatigue crack initiation and propagation in the very high cycle fatigue regime of high-strength steels. Scripta Mater. 2012;67:838–841. doi: 10.1016/j.scriptamat.2012.07.049
11.
Stanzl-TscheggSE, SchonbauerB.Mechanisms of strain localization, crack initiation and fracture of polycrystalline copper in the VHCF regime. Int J Fatigue. 2010;32:886–893. doi: 10.1016/j.ijfatigue.2009.03.016
12.
ChaiGC, PengRL, JohanssonS.Micro fatigue crack propagation behavior in a duplex stainless steel studied using in-situ SEM/EBSD method. In: ClarkG, WangCH, editors. Adv Mater Res. 2014;891–892:313–318. doi: 10.4028/www.scientific.net/AMR.891-892.313
13.
TofiqueMW, BergstromJ, BurmanC, Fatigue strength, crack initiation, and localized plastic fatigue damage in VHCF of Duplex stainless steels. Steel Res Int. 2016;87:899–910. doi: 10.1002/srin.201500263
14.
KruppU, SokerM, GiertlerA, The potential of spinodal ferrite decomposition for increasing the very high cycle fatigue strength of duplex stainless steel. Int J Fatigue. 2016;93:363–371. doi: 10.1016/j.ijfatigue.2016.05.012
15.
DongesB, IstominK, SokerM, Experimental investigation and numerical description of the damage evolution in a duplex stainless steel subjected to VHCF-loading. Mat Sci Eng a-Struct. 2015;646:8–18. doi: 10.1016/j.msea.2015.08.021
16.
PapakyriacouM, MayerH, FuchsU, Influence of atmospheric moisture on slow fatigue crack growth at ultrasonic frequency in aluminium and magnesium alloys. Fatigue Fract Eng M. 2002;25:795–804. doi: 10.1046/j.1460-2695.2002.00571.x
17.
NovýF, JanečekM, ŠkoríkV, Very high cycle fatigue behaviour of as-extruded AZ31, AZ80, and ZK60 magnesium alloys. Int J Mater Res. 2009;100:288–291. doi: 10.3139/146.110043
18.
AdamsJF, AllisonJE, JonesJW.The effects of heat treatment on very high cycle fatigue behavior in hot-rolled WE43 magnesium. Int J Fatigue. 2016;93:372–386. doi: 10.1016/j.ijfatigue.2016.05.033
19.
MurakamiY, UsukiH.Quantitative evaluation of effects of non-metallic inclusions on fatigue strength of high strength steels. II: Fatigue limit evaluation based on statistics for extreme values of inclusion size. Int J Fatigue. 1989;11:299–307. doi: 10.1016/0142-1123(89)90055-8
20.
BathiasC.Piezoelectric fatigue testing machines and devices. Int J Fatigue. 2006;28:1438–1445. doi: 10.1016/j.ijfatigue.2005.09.020
21.
LiuW, DongJ, ZhangP, High cycle fatigue behavior of as-extruded ZK60 magnesium alloy. J Mater Sci. 2009;44:2916. doi: 10.1007/s10853-009-3385-z
22.
SakaiT, LianB, TakedaM, Statistical duplex S–N characteristics of high carbon chromium bearing steel in rotating bending in very high cycle regime. Int J Fatigue. 2010;32:497–504. doi: 10.1016/j.ijfatigue.2009.08.001
23.
BathiasC.There is no infinite fatigue life in metallic materials. Fatigue Fract Eng Mater Struct. 1999;22:559–565. doi: 10.1046/j.1460-2695.1999.00183.x
24.
YooM.Slip, twinning, and fracture in hexagonal close-packed metals. Metall Trans A. 1981;12:409–418. doi: 10.1007/BF02648537
25.
YangF, YinS, LiS, Crack initiation mechanism of extruded AZ31 magnesium alloy in the very high cycle fatigue regime. Mater Sci Eng A. 2008;491:131–136. doi: 10.1016/j.msea.2008.02.003
26.
JordonJ, GibsonJ, HorstemeyerM, Effect of twinning, slip, and inclusions on the fatigue anisotropy of extrusion-textured AZ61 magnesium alloy. Mater Sci Eng A. 2011;528:6860–6871. doi: 10.1016/j.msea.2011.05.047
27.
WuL, JainA, BrownD, Twinning–detwinning behavior during the strain-controlled low-cycle fatigue testing of a wrought magnesium alloy, ZK60A. Acta Mater. 2008;56:688–695. doi: 10.1016/j.actamat.2007.10.030
28.
KruppU, GiertlerA, SökerM, The behavior of short fatigue cracks during very high cycle (VHCF) fatigue of duplex stainless steel. Eng Fract Mech. 2015;145:197–209. doi: 10.1016/j.engfracmech.2015.03.024
29.
IstominK, DöngesB, SchellN, Analysis of VHCF damage in a duplex stainless steel using hard X-ray diffraction techniques. Int J Fatigue. 2014;66:177–182. doi: 10.1016/j.ijfatigue.2014.04.001
30.
ShiozawaK, KashiwagiT, MuraiT, Fatigue behaviour and fractography of extruded AZ80 magnesium alloys in very high cycle regime. Procedia Eng. 2010;2:183–191. doi: 10.1016/j.proeng.2010.03.020
31.
LiuX, SunC, HongY.Faceted crack initiation characteristics for high-cycle and very-high-cycle fatigue of a titanium alloy under different stress ratios. Int J Fatigue. 2016;92:434–441. doi: 10.1016/j.ijfatigue.2016.03.013
32.
HuangZY, LiuHQ, WangHM, Effect of stress ratio on VHCF behavior for a compressor blade titanium alloy. Int J Fatigue. 2016;93:232–237. doi: 10.1016/j.ijfatigue.2016.05.004
33.
NikitinA, Palin-LucT, ShanyavskiyA.Crack initiation in VHCF regime on forged titanium alloy under tensile and torsion loading modes. Int J Fatigue. 2016;93:318–325. doi: 10.1016/j.ijfatigue.2016.05.030
34.
OchiY, MatsumuraT, MasakiK, High-cycle rotating bending fatigue property in very long-life regime of high-strength steels. Fatigue Fract Eng M. 2002;25:823–830. doi: 10.1046/j.1460-2695.2002.00575.x
35.
HongYS, LiuXL, LeiZQ, The formation mechanism of characteristic region at crack initiation for very-high-cycle fatigue of high-strength steels. Int J Fatigue. 2016;89:108–118. doi: 10.1016/j.ijfatigue.2015.11.029
36.
CavaliereP, De MarcoP.Superplastic behaviour of friction stir processed AZ91 magnesium alloy produced by high pressure die cast. J Mater Process Tech. 2007;184:77–83. doi: 10.1016/j.jmatprotec.2006.11.005
37.
TanakaK, AkiniwaY.Fatigue crack propagation behaviour derived from S–N data in very high cycle regime. Fatigue Fract Eng M. 2002;25:775–784. doi: 10.1046/j.1460-2695.2002.00547.x
38.
HertzbergRW.Deformation and fracture mechanics of engineering materials. 3rd ed. New York (NY): Wiley; 1989.
39.
NixWD, GaoH.Indentation size effects in crystalline materials: a law for strain gradient plasticity. J Mech Phys Solids. 1998;46:411–425. doi: 10.1016/S0022-5096(97)00086-0
40.
MurakamiY, EndoM.Effects of defects, inclusions and inhomogeneities on fatigue strength. Int J Fatigue. 1994;16:163–182. doi: 10.1016/0142-1123(94)90001-9
41.
ChapettiM, TagawaT, MiyataT.Ultra-long cycle fatigue of high-strength carbon steels part II: estimation of fatigue limit for failure from internal inclusions. Mater Sci Eng A. 2003;356:236–244. doi: 10.1016/S0921-5093(03)00136-9
42.
MayerH, HaydnW, SchullerR, Very high cycle fatigue properties of bainitic high carbon–chromium steel. Int J Fatigue. 2009;31:242–249. doi: 10.1016/j.ijfatigue.2008.09.001
43.
ParisPC, TadaH, DonaldJK.Service load fatigue damage – a historical perspective. Int J Fatigue. 1999;21:S35–S46. doi: 10.1016/S0142-1123(99)00054-7
44.
HongY, LeiZ, SunC, Propensities of crack interior initiation and early growth for very-high-cycle fatigue of high strength steels. Int J Fatigue. 2014;58:144–151. doi: 10.1016/j.ijfatigue.2013.02.023
