Experimental fatigue characterization and elasto-plastic finite element analysis of notched specimens made of direct-quenched ultra-high-strength steel
Restricted accessResearch articleFirst published online November, 2017
Experimental fatigue characterization and elasto-plastic finite element analysis of notched specimens made of direct-quenched ultra-high-strength steel
The low-cycle fatigue behavior of a direct-quenched ultra-high-strength steel was experimentally characterized and numerically modeled. Fatigue and cyclic parameters were obtained by conducting strain-controlled low-cycle fatigue tests on uniform-gage specimens. Surface residual stresses were minimized and axial deflection eliminated by optimization of machining parameters and post-machining electro-polishing. The steel material showed cyclic softening and decrease in yield strength. Cyclic softening, stabilized response, and the cyclic stress–strain curve were numerically simulated using finite element analysis with a model capable of describing nonlinear kinematic-isotropic hardening. The results showed good agreement with experimental values and validated the model’s ability to simulate the softening and cyclic stabilization of the material under investigation. The same numerical method was then used in elasto-plastic stress–strain analysis of notched specimens made of the same material to make fatigue life predictions. Estimated lives were compared with predictions made by analytical approximations such as the linear rule, Neuber’s rule, and the strain energy density method and verified by experimental data. Finite element analysis using stabilized cyclic response yields the most accurate predictions and, thus, provides an effective tool for the fatigue analysis of this material.
PolakJ. Cyclic plasticity and low cycle fatigue life of metals, Amsterdam: Elsevier Science Publishing Inc., 1991.
2.
NeuberH. Theory of stress concentration for shear-strained prismatical bodies with arbitrary nonlinear stress strain laws. J Appl Mech-T ASME1961; 28: 544–550.
3.
MolskiKGlinkaG. A method of elastic-plastic stress and strain calculation at a notch root. Mater Sci Eng1981; 50: 93–100.
4.
Mowbray DF and McConnelee JE. Applications of finite element stress analysis and stress-strain properties in determining notch fatigue specimen deformation and life. In: Cyclic stress-strain behavior-analysis, experimentation, and failure prediction. West Conshohocken, PA: American Society for Testing and Materials, 1973, pp.151–169.
5.
Jhansale HR and Topper TH. Engineering analysis of the inelastic stress response of a structural metal under variable cyclic strains. In: Cyclic stress-strain behavior-analysis, experimentation, and failure prediction. West Conshohocken, PA: American Society for Testing and Materials, 1973, pp.246–270.
6.
DowlingNE. Fatigue life prediction for complex load versus time histories. J Eng Mater-T ASME1983; 105: 206–214.
7.
HoffmannMSeegerT. A generalized method for estimating multiaxial elastic-plastic notch stresses and strains part 1: Theory. J Eng Mater-T ASME1985; 107: 250–255.
8.
Hoffmann M and Seeger T. Stress-strain analysis and life predictions of a notched shaft. In: Multiaxial fatigue: Analysis and experiments, Society of Automotive Engineers, 1989.
9.
Cronvall O. Numerical modelling of low-cycle fatigue behaviour of austenitic stainless piping steels. VTT Technical Research Centre of Finland, Espoo, 2004.
10.
Humayun KabirSMYeoT. Characterization of unified material parameters in elasto-plastic continuum approach. Int Rev Mech Eng2010; 4: 507–517.
11.
LiBReisLde FreitasM. Simulation of cyclic stress/strain evolutions for multiaxial fatigue life prediction. Int J Fatigue2006; 28: 451–458.
12.
KömiJKarjalainenPPorterD. Direct-quenched structural steels. Encyclopedia of iron, steel, and their alloys, Boca Raton, FL: CRC Press, 2016.
13.
ASTM Standard E606. Standard test method for straincontrolled fatigue testing. West Conshohocken, PA: American Society for Testing and Materials, 2013.
14.
KurodaMMarrowTJ. Preparation of fatigue specimens with controlled surface characteristics. J Mater Process Technol2008; 203: 396–403.
15.
ASTM Standard E739. Standard practice for statistical analysis of linear or linearized stress-life (S-N) and strain-life (ɛ-N) fatigue data, West Conshohocken, PA: American Society for Testing and Materials, 2004.
16.
DowlingNE. Mechanical behavior of materials: Engineering methods for deformation, fracture and fatigue, 4th ed. Upper Saddle River, NJ: Pierson Prentice Hall, 2013.
17.
StephensRIFatemiAStephensRRet al.Metal fatigue in engineering, 2nd ed. New York: John Wiley & Sons, 2001.
18.
Masing G. Eigenspannungen und verfestigung beim messing. In: 2nd International congress of applied mechanics, Zurich, 1926.
19.
MuralidharanMMansonS. Modified universal slopes equation for estimation of fatigue characteristics. J Eng Mater-T ASME1988; 110: 55–58.
20.
RoessleMLFatemiA. Strain-controlled fatigue properties of steels an some simple approximations. Int J Fatigue2000; 22: 495–511.
21.
DabiriMLaukkanenABjörkT. Fatigue microcrack nucleation modeling: A survey of the state of the art. Int Rev Mech Eng2015; 9: 368–376.
22.
MrózZ. On the description of anisotropic workhardening. J Mech Phys Solids1967; 15: 163–175.
23.
CostaJDMAntunesFJVSilvaVRet al.Comparative analysis of fatigue life predictions in central notched specimens of Al–Mg–Si alloys. Fatigue Fract Eng M2004; 27: 837–848.
24.
SusmelLTaylorD. Estimating lifetime of notched components subjected to variable amplitude fatigue loading according to the elastoplastic theory of critical distances. J Eng Mater-T ASME2015; 137: 011008–011008-15.
25.
BarkeyMESocieDFHsiaKJ. A yield surface approach to the estimation of notch strains for proportional and nonproportional cyclic loading. J Eng Mater-T ASME1994; 116: 173–180.
EllyinF. Fatigue damage, crack growth and life prediction, London, UK: Chapman & Hall, 1997.
28.
Sarajärvi U and Cronvall O. Simulation and analysis of data for enhancing low cycle fatigue test procedures. VTT Technical Research Centre of Finland, Espoo, 2006.
29.
FrickeW. IIW recommendations for the fatigue assessment of welded structures by notch stress analysis, Cambridge, UK: Woodhead Publishing, 2012.
30.
TopperTHWetzelRMMorrowJD. Neuber’s rule applied to fatigue of notched specimens. J Mater1969; 4.
31.
PetersonRE. Stress concentration factors, New York: John Wiley & Sons, 1974.
SiebelEStielerM. Significance of dissimilar stress distributions for cyclic loading. Zeitschr VDI1975; 97: 146–148.
34.
SchijveJ. Fatigue of structures and materials, 2nd ed. Delft, The Netherlands: Springer, 2009.
35.
PilkeyWDPilkeyDF. Peterson’s stress concentration factors, 3rd ed. New York: John Wiley & Sons, 2008.
36.
YoungWCBudynasRG. Roark’s formulas for stress and strain, 7th ed. New York: McGraw-Hill, 2002.
37.
ZengZFatemiA. Elasto-plastic stress and strain bahaviour at notch roots under monotonic and cyclic loadings. J Strain Anal Eng2001; 36: 287–300.
38.
HärkegårdGMannT. Neuber prediction of elasto-plastic strain concentration in notched tensile specimens under large-scale yielding. J Strain Anal Eng2003; 38: 79–94.
39.
FatemiAZengZPlaseiedA. Fatigue behavior and life predictions of notched specimens made of QT and forged microalloyed steels. Int J Fatigue2004; 26: 663–672.
40.
Wirsching PH and Ortiz K. Reliability methods in mechanical and structural design. In: 18th annual seminar and workshop, University of Arizona, Tucson, AZ, USA, 1996.
