Abstract
The increasing incidence of military aircraft engine failures that can be traced to high-cycle fatigue (HCF) has prompted a reassessment of the design methodologies for HCF-critical components, such as turbine blades and disks. Because of the high-frequency vibratory loading involved, damagetolerant design methodologies based on a threshold for no crack growth offer a preferred approach. As impact damage from ingested debris is a prime source of HCF-related failures, the current study is focused on the role of such foreign-object damage (FOD) in influencing fatigue crack-growth thresholds and early crack growth of both large and small cracks in a fan blade alloy, Ti-6Al-4V. FOD, which was simulated by the high-velocity (200 to 300 m/s) impact of steel spheres on a flat surface, was found to reduce markedly the fatigue strength, primarily due to earlier crack initiation. This is discussed in terms of four salient factors: (1) the stress concentration associated with the FOD indentation, (2) the presence of small microcracks in the damaged zone, (3) the localized presence of tensile residual hoop stresses at the base and rim of the indent sites, and (4) microstructural damage from FOD-induced plastic deformation. It was found that no crack growth occurred from FOD impact sites in this alloy at ΔK values below ∼ 2.9 MPa √m, i.e., over 50 pct higher than the “closure-free”, worst-case threshold value of ΔK TH = 1.9 MPa √m, defined for large cracks in bimodal Ti-6Al-4V alloys at the highest possible load ratio. It is, therefore, concluded that such worst-case, large fatigue crack thresholds can, thus, be used as a practical lower-bound to FOD-initiated cracking in this alloy.
Similar content being viewed by others
References
B.A. Cowles: Int. J. Fract., 1996, vol. 80, pp. 147–63.
T. Nicholas and J.R. Zuiker: Int. J. Fract., 1996, vol. 80, pp. 219–35.
J.M. Larsen, B.D. Worth, C.G. Annis, Jr., and F.K. Haake: Int. J. Fract., 1996, vol. 80, pp. 237–55.
R.O. Ritchie: Proc. ASME Aerospace Division, J.C.I. Chang, J. Coulter, D. Brei, W.H.G. Martinez, and P.P. Friedmann, eds., ASME, Fairfield, NJ, 1996, AD-vol. 52, pp. 321–33.
Erosion, Corrosion and Foreign Object Damage Effects in Gas Turbines, AGARD Conf. Proc. No. 558, North Atlantic Treaty Organization, Advisory Group for Aerospace Research and Development, Propulsion and Energetics Panel, Neully-sur-Seine, France, 1994.
T. Nicholas, J.P. Barber, and R.S. Bertke: Exp. Mech., 1980, Oct., pp 357–64.
S.J. Hudak, Jr., G.G. Chell, T.S. Rennick, R.C. McClung, and D.L. Davidson: Proc. 4th Nat. Turbine Engine HCF Conf., CD Rom, Session 10, Materials Damage Tolerance IV, 1999, pp. 7–17.
P. Gravett, R. Bellows, T. Dunyak, D. Herrmann, and S. Hudak, Jr.: Proc. 4th Nat. Turbine Engine HCF Conf., CD Rom, Session 10, Materials Damage Tolerance IV, 1999, pp. 1–6.
O. Roder, J.O. Peters, B.L. Boyce, A.W. Thompson, and R.O. Ritchie: Proc. 4th Nat. Turbine Engine HCF Conf., CD Rom, Session 10, Materials Damage Tolerance IV, 1999, pp. 41–50.
R.O. Ritchie, D.L. Davidson, B.L. Boyce, J.P. Campbell, and O. Roder: Fat. Fract. Eng. Mater. Struct., 1999, vol. 22, pp. 621–31.
N.E. Frost: Proc. Inst. Mech. Eng., 1959, vol. 173, pp. 811–27.
N.E. Dowling: Fat. Eng. Mat. Struct., 1979, vol. 2, pp. 129–39.
M.H. El Haddad, T.H. Topper, and K.N. Smith: Eng. Fract. Mech., 1979, vol. 11, pp. 573–84.
T.S. Harding, J.W. Jones, P.S. Steiff, and T.M. Pollock: Scripta Mater., 1999, vol. 40, pp. 445–49.
J.L. Hamrick II, S. Mall, and T. Nicholas: Proc. 4th Nat. Turbine Engine HCF Conf., CD Rom, Session 8, Materials Damage Tolerance IV, 1999, pp. 38–48.
V. Gros, B.A. Taweel, M. Ceretti, C. Prioul, and A. Lodini: Proc. 4th Eur. Conf. on Residual Stresses, S. Denis, J.-L. Lebrun, B. Bourniquel, M. Barral, and J.-F. Flavenot, eds., SF2M, ENSAM, Cluny en Bourgogne, France, 1996, pp. 567–75.
J.J. Ruschau, S.R. Thompson, J.J. Kleck, and T. Nicholas: Proc. 4th Nat. Turbine Engine HCF Conf., CD Rom, Session 8, Materials Damage Tolerance IV, 1999, pp. 28–37.
K.-P. Hornauer, H.H. Jühe, A. Klinkenberg, and P. Starker: Härtereitechnische Mitteilungen, 1981, vol. 36, pp. 322–26.
M. Kobayashi, T. Matsui, and Y. Murakami: Int. J. Fatigue, 1998, vol. 20, pp. 351–57.
G.B. Sinclair, P.S. Follansbee, and K.L. Johnson: Int. J. Solids Struct., 1985, vol. 21, pp. 865–88.
X. Chen and J.W. Hutchinson: “Foreign Object Damage and Fatigue Cracking on the Shallow Indentation,” Harvard University Report No. ME 358, Cambridge, MA, Nov. 1999.
C. Hardy, C.N. Baronet, and G.V. Tordion: Int. J. Num. Meth. Eng., 1971, vol. 3, pp. 451–62.
C.J. Studman and J.E. Field: J. Mater. Sci., 1977, vol. 12, pp. 215–18.
G. Lütjering: Mater. Sci. Eng., 1998, vol. A243, pp. 32–45.
A.W. Thompson: in Fatigue Behavior of Titanium Alloys, R.R. Boyer, D. Eylon, and G. Lütjering, eds., TMS, Warrendale, PA, 1999, pp. 23–31.
W.J. Evans: Mater. Sci. Eng., 1999, vol. A263, pp. 160–75.
L. Wagner and G. Lütjering: Proc. 2nd Int. Conf. Shot Peening, H.O. Fuchs, ed., American Shot Peening Society, Paramus, NJ, 1984, pp. 194–200.
L. Wagner and G. Lütjering: Proc. 2nd Int. Conf. Shot Peening, H.O. Fuchs, ed., American Shot Peening Society, Paramus, NJ, 1984, pp. 201–07.
H. Gray, L. Wagner, and G. Lütjering: in Shot Peening, H. Wohlfahrt, R. Kopp, and O. Vöhringer, eds., DGM, Oberursel, Germany, 1987, p. 467.
D. Eylon: “Summary of the Available Information on the Processing of the Ti-6Al-4V HCF/LCF Program Plates,” University of Dayton Report, University of Dayton, Dayton, OH, 1998.
J.C. Newman, Jr. and I.S. Raju: Eng. Fract. Mech., 1981, vol. 15, pp. 185–92.
J.M. Morgan and W.W. Milligan: in High Cycle Fatigue of Structural Materials, W.O. Soboyejo and T.S. Srivatsan, eds., TMS, Warrendale, PA, 1997, pp. 305–12.
R.O. Ritchie and W. Yu: in Small Fatigue Cracks, R.O. Ritchie and J. Landford, eds., TMS, Warrendale, PA, 1986, pp. 167–89.
A. Coles, R.E. Johnson, and H.G. Popp: J. Eng. Mater. Technol., 1976, pp. 305–15.
M. Nisida and P. Kim: Proc. 12th Nat. Congr. Applied Mechanics, 1962, pp. 69–74.
P. Lukáš: Eng. Fract. Mech., 1987, vol. 26, pp. 471–73.
I.M. Hutchings: in Materials Behavior under High Stress and Ultra High Loading Rates, J. Mescall and V. Weiss, eds., Plenum Press, New York, NY, 1983, pp. 161–96.
S.P. Timothy and I.M. Hutchings: Acta Metall., 1985, vol. 33, pp. 667–76.
S.P. Timothy and I.M. Hutchings: Eng. Fract. Mech., 1984, vol. 7, pp. 223–27.
S.P. Timothy and I.M. Hutchings: Proc. of the 3rd Conf. on the Mechanical Properties of Materials at High Rates of Strain, The Institute of Physics, London, 1984, pp. 397–404.
J.A. Hines, J.O. Peters, and G. Lütjering: in Fatigue Behavior of Titanium Alloys, R.R. Boyer, D. Eylon, and G. Lütjering, eds., TMS, Warrendale, PA, 1999, pp. 15–22.
J. Goodman: Mechanics Applied to Engineering, Longmans, Green & Co., Ltd., London, 1899.
Small Fatigue Cracks, R. O. Ritchie and J. Lankford, eds., TMS-AIME, Warrendale, PA, 1986.
The Behaviour of Short Fatigue Cracks, K.J. Miller and E.R. de los Rios, eds., The Mechanical Engineering Publishing Ltd., London, 1986.
Short Fatigue Cracks, K.J. Miller and E.R. de los Rios, eds., The Mechanical Engineering Publishing Ltd., London, 1992.
R.O. Ritchie and J. Landford: Mater. Sci. Eng., 1986, vol. 84, pp. 11–16.
R.O. Ritchie, B.L. Boyce, J.P. Campbell, O. Roder, A.W. Thompson, and W.W. Milligan: Int. J. Fatigue, 1999, vol. 21, pp. 653–62.
J.A. Hines, J.O. Peters, and G. Lütjering: Proc. 9th World Congr. on Titanium, I. Gorynin, ed., TMS, Warrendale, PA, 1999, in press.
J.O. Peters, A. Gysler, and G. Lütjering: Proc. ICAA-6, Aluminum Alloys, T. Sato, S. Kumai, T. Kobayashi, and Y. Murakami, eds., Japan Inst. Light Metals, Tokyo, Japan, 1998, vol. 3, pp. 147–32.
J.O. Peters, A. Gysler, and G. Lütjering: Fatigue ’99, Proc. 7th Int. Congr. on Fatigue, X.-R. Wu and Z.-G. Wang, eds., Higher Education Press, Beijing/EMAS Ltd., Warley, United Kingdom, 1999, vol. 2, pp. 1009–14.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Peters, J.O., Boyce, B.L., Thompson, A.W. et al. Role of foreign-object damage on thresholds for high-cycle fatigue in Ti-6Al-4V. Metall Mater Trans A 31, 1571–1583 (2000). https://doi.org/10.1007/s11661-000-0167-2
Received:
Issue Date:
DOI: https://doi.org/10.1007/s11661-000-0167-2