In this study, a novel method stress wave strengthening (SWS) process based on electromagnetic force was proposed to improve the fatigue life of holed structures. Corresponding tests were carried out to explore the fatigue performance of SWS. Cold expansion (CE) was also investigated for comparison. The fatigue life of SWS and CE samples were evaluated, moreover, the mechanisms of fatigue failures and life enhancements were also discussed. Results showed that double-side SWS extended fatigue life significantly and reduced stiffness degradation more effectively with respect to CE process. Moreover, fatigue cracks commonly appeared at mid-planes of hole surfaces and horizontally grew in SWS samples, which differed a lot from CE samples. Through the residual stress measurement, it is seen that more uniform residual stress along axial direction can be obtained by SWS compared to CE, which can explain the fatigue life enhancement and failure mechanism of SWS method.
AkpinarSAydinMDÖzelA. A study on 3-D stress distributions in the bi-adhesively bonded T-joints. Appl Math Model2013; 37: 10220–10230.
2.
CaoYCaoZZuoY, et al.Numerical and experimental investigation of fitting tolerance effects on damage and failure of CFRP/Ti double-lap single-bolt joints. Aerosp Sci Technol2018; 78: 461–470.
3.
GorjipoorAHoaSVGanesanR. Numerical model for investigation of the strain distribution in thick composite plates subjected to bolt loads. Aerosp Sci Technol2016; 59: 94–102.
4.
ScarselliGCastoriniEPanellaFW, et al.Structural behaviour modelling of bolted joints in composite laminates subjected to cyclic loading. Aerosp Sci Technol2015; 43: 89–95.
JenYM. Fatigue life evaluation of adhesively bonded scarf joints. Int J Fatigue2012; 36: 30–39.
7.
HuangWWangTJGarbatovY, et al.Fatigue reliability assessment of riveted lap joint of aircraft structures. Int J Fatigue2012; 43: 54–61.
8.
SkorupaASkorupaMMachniewiczT, et al.Fatigue crack location and fatigue life for riveted lap joints in aircraft fuselage. Int J Fatigue2014; 58: 209–217.
9.
FuYGeESuH, et al.Cold expansion technology of connection holes in aircraft structures: a review and prospect. Chin J Aeronaut2015; 28(4): 961–973.
10.
LiuJYueZFLiuYS. Surface finish of open holes on fatigue life. Theor Appl Fract Mech2007; 47(1): 35–45.
11.
GongPZhengLBZhangK. Effects of hole cold expansion on microstructure and fatigue property of 7B50-T7451 aluminum alloy plate. J Aeronaut Mater2011; 31: 45–50.
12.
ChakherlouTNVogwellJ. A novel method of cold expansion which creates near-uniform compressive tangential residual stress around a fastener hole. Fatigue Fract Eng Mater Struct2003; 27: 343–351.
13.
LiuJShaoXJLiuYS, et al.Effect of cold expansion on fatigue performance of open holes. Mater Sci Eng A2008; 477(1–2): 271–276.
14.
KarabinMEBarlatFSchultzRW. Numerical and experimental study of the cold expansion process in 7085 plate using a modified split sleeve. J Mater Process Technol2007; 189: 45–57.
15.
AbrahamBCarmelM. The effects of residual tensile stresses induced by cold working a fastener hole. In: USAF aircraft structural integrity program conference, US, January2007.
16.
PastaS. Fatigue crack propagation from a cold-worked hole. Eng Fract Mech2007; 74: 1525–1538.
17.
MatosPFPMcEvilyAJMoreiraPMGP, et al.Analysis of the effect of cold-working of rivet holes on the fatigue life of an aluminum alloy. Int J Fatigue2007; 29: 575–586.
18.
LacaracVDGarcia-GranadaAASmithDJ, et al.Prediction of the growth rate for fatigue cracks emanating from cold expanded holes. Int J Fatigue2004; 26: 585–595.
19.
FaghihSShahaSKBehraveshSB, et al.Split sleeve cold expansion of AZ31B sheet: microstructure, texture and residual stress. Mater Des2020; 186: 108213.
20.
YanWZWangXSGaoHS, et al.Effect of split sleeve cold expansion on cracking behaviors of titanium alloy TC4 holes. Eng Fract Mech2012; 88: 79–89.
21.
JoseCCMartaMMEvaMR, et al.Parametric analysis of the mandrel geometrical data in a cold expansion process of small holes drilled in thick plates. Mater2019; 12(24): 4105.
22.
RahmanS. Total fatigue lives, crack growth paths and cycles in cold expanded adjacent holes. Int J Fatigue2018; 119: 69–77.
23.
SunYHuWShenF, et al.Numerical simulations of the fatigue damage evolution at a fastener hole treated by cold expansion or with interference fit pin. Int J Mech Sci2016; 107: 188–200.
24.
WangYZhuYHouS, et al.Investigation on fatigue performance of cold expansion holes of 6061-T6 aluminum alloy. Int J Fatigue2017; 95: 216–228.
25.
GeiglouZChakherlouTN. Investigating the effect of cold expansion process on the fatigue behavior of aluminum alloy 7075-T6 in double-lap shear joints. P I Mech Eng L-J Mat2018; 233(8): 1645–1660.
26.
AbdulKSXiangZJamesE, et al.Fatigue performance of bonded crack retarders in the presence of cold worked holes and interference-fit fasteners. Int J Fatigue2017; 105: 111–118.
27.
LiuHHuaDWangaR, et al.Experimental and numerical investigations on the influence of cold expansion on low cycle fatigue life of bolt holes in aeroengine superalloy disk at elevated temperature. Int J Fatigue2020; 132: 105390.
28.
ChakherlouTNTaghizadehHAghdamAB. Experimental and numerical comparison of cold expansion and interference fit methods in improving fatigue life of holed plate in double shear lap joints. Aerosp Sci Technol2013; 29(1): 351–362.
29.
SemariZAidABenhamenaA, et al.Effect of residual stresses induced by cold expansion on the crack growth in 6082 aluminum alloy. Eng Fract Mech2013; 99: 159–168.
30.
GopalakrishnaHDNarasimha MurthyHNKrishnaM, et al.Cold expansion of holes and resulting fatigue life enhancement and residual stresses in Al 2024 T3 alloy-An experimental study. Eng Fail Anal2010; 99: 361–368.
31.
ZhouZFuaJCaoQ, et al.Electromagnetic cold-expansion process for circular holes in aluminum alloy sheets. J Mater Process Technol2017; 248: 49–55.
32.
ZhouZFuaJCaoQ, et al.A novel hole cold-expansion method and its effect on surface integrity of nickel-based superalloy. J Mater Sci Technol2020; 59: 129–137.
33.
MaximovJTDunchevaGVAmudjevIM. A novel method and tool which enhance the fatigue life of structural components with fastener holes. Eng Fail Anal2013; 31: 132–143.
34.
MaximovJTDunchevaGVAnchevAP, et al.New method and tool for increasing fatigue life of a large number of small fastener holes in 2024-T3 Al alloy. J Braz Soc Mech Sci2019; 41(4): 203.
35.
DunchevaGVMaximovJTGanevN. A new conception for enhancement of fatigue life of large number of fastener holes in aircraft structures. Fatigue Fract Eng Mater Struct2017; 40(2): 176–189.
36.
MaximovJTDunchevaGVAmudjevIM, et al.A new approach for pre-stressing of rail-end-bolt holes. Proc Inst Mech Eng C J Mec Eng Sci2017; 231(12): 2275–2283.
37.
WangYZhuYCaiZ. Effect of ultrasonic impact treatment on the fatigue performance of cold expanded AA6061-T6 hole. J Mater Eng Perform2020; 29(1): 691–698.
38.
ZhengGCaoZZuoY. A dynamic cold expansion method to improve fatigue performance of holed structures based on electromagnetic load. Int J Fatigue2021; 148: 106253.
39.
ReinhallPGGhassaeiSChooV. An analysis of rivet die design in electromagnetic riveting. J Vib Acoust Stress Reliab Des1988; 110: 65.
40.
ZuoYCaoZZhengG, et al.Damage behavior investigation of CFRP/Ti bolted joint during interference fit bolt dynamic installation progress. Eng Fail Anal2020; 111: 104454.
41.
ZhangQCaoZQinL, et al.Numerical simulation of electromagnetic riveting for titanium alloy. Rare Metal Mater Eng2013; 42(9): 1832–1837.
