In this paper, scatter in crack growth for dwell time loadings in combination with overloads has been investigated. Multiple tests were performed for surface cracks at 550 °C in the commonly used high temperature material Inconel 718. The test specimens originate from two different batches which also provide for a discussion of how material properties affect the dwell time damage and overload impact. In combination with these tests, an investigation of the microstructure was also carried out, which shows how it influences the growth rate. The results from this study show that, in order to take overloads into consideration when analyzing spectrum loadings containing dwell times, one needs a substantial amount of material data available as the scatter seen from one batch to the other are of significant proportions.
Issue Section:
Gas Turbines: Structures and Dynamics
References
1.
Larsen
, J.
, and Nicholas
, T.
, 1983
, “Load Sequence Crack Growth Transients in a Superalloy at Elevated Temperature
,” 14th National Symposium on Fracture Mechanics, Los Angeles, CA, June 30–July 2, Vol. II: Testing and Applications
, ASTM STP 791, pp. II-536
–II-552
.2.
Nicholas
, T.
, and Weerasooriya
, T.
, 1986
, “Hold-Time Effects in Elevated Temperature Fatigue Crack Propagation
,” 17th National Symposium on Fracture Mechanics, ASTM STP 905, Albany, NY, Aug. 7–9, 1984, pp. 155
–168
.3.
Weerasooriya
, T.
, 1987
, “Effect of Frequency on Fatigue Crack Growth Rate of Inconel 718 at High Temperature
,” Air Force Wright Aeronautical Laboratories Report, Wright-Patterson Air Force Base, OH, Technical Report No. AFWAL-TR-87-4038.4.
Andrieu
, E.
, Molins
, R.
, Ghonem
, H.
, and Pineau
, A.
, 1992
, “Intergranular Crack Tip Oxidation Mechanism in a Nickel-Based Superalloy
,” Mater. Sci. Eng., A
, 154
(1
), pp. 21
–28
.5.
Ghonem
, H.
, Nicholas
, T.
, and Pineau
, A.
, 1993
, “Elevated Temperature Fatigue Crack Growth in Alloy 718—Part I: Effects of Mechanical Variables
,” Fatigue Fract. Eng. Mater. Struct.
, 16
(5
), pp. 565
–576
.6.
Krupp
, U.
, 2005
, “Dynamic Embrittlement—Time-Dependent Quasi-Brittle Intergranular Fracture at High Temperatures
,” Int. Mater. Rev.
, 50
(2
), pp. 83
–97
.7.
Woodford
, D. A.
, 2006
, “Gas Phase Embrittlement and Time Dependent Cracking of Nickel Based Superalloys
,” Energy Mater.
, 1
(1
), pp. 59
–79
.8.
Ghonem
, H.
, and Zheng
, D.
, 1992
, “Depth of Intergranular Oxygen Diffusion During Environment-Dependent Fatigue Crack Growth in Alloy 718
,” Mater. Sci. Eng., A
, 150
(2
), pp. 151
–160
.9.
Molins
, R.
, Hochstetter
, G.
, Chassaigne
, J. C.
, and Andrieu
, E.
, 1997
, “Oxidation Effects on the Fatigue Crack Growth Behaviour of Alloy 718 at High Temperature
,” Acta Mater.
, 45
(2
), pp. 663
–674
.10.
Liu
, X. B.
, Ma
, L. Z.
, Chang
, K. M.
, and Barbero
, E.
, 2005
, “Fatigue Crack Propagation of Ni-Based Superalloys
,” Acta Metall. Sin.
, 18
(1
), pp. 55
–64
.11.
Gustafsson
, D.
, and Lundström
, E.
, 2013
, “High Temperature Fatigue Crack Growth Behaviour of Inconel 718 Under Hold Time and Overload Conditions
,” Int. J. Fatigue
, 48
, pp. 178
–186
.12.
Ponnelle
, S.
, Brethes
, B.
, and Pineau
, A.
, 2002
, “High Temperature Fatigue Crack Growth Rate in Inconel 718: Dwell Effect Annihilations
,” European Structural Integrity Society
, Elsevier, Vol. 29
, pp. 257
–266
.13.
Nicholas
, T.
, Haritos
, G.
, Hastie
, R.
, Jr., and Harms
, K.
, 1991
, “The Effect of Overloads on Sustained-Load Crack Growth in a Nickel-Base Superalloy: Part II—Experiments
,” Theor. Appl. Fract. Mech.
, 16
(1
), pp. 51
–62
.14.
Wanhill
, R.
, 2002
, “Significance of Dwell Cracking for IN718 Turbine Discs
,” Int. J. Fatigue
, 24
(5
), pp. 545
–555
.15.
ASTM
, 2008
, “Standard Test Method for Measurement of Fatigue Crack Growth Rates
,” ASTM International
, West Conshohocken, PA
, ASTM Standard No. E647-08.16.
Newman
, J. C.
, Jr., and Raju
, I. S.
, 1984
, “Stress-Intensity Factor Equations for Cracks in Three-Dimensional Finite Bodies Subjected to Tension and Bending Loads
,” NASA Langley Research Center, Hampton, VA, NASA Technical Memorandum No. 85793.17.
Lundström
, E.
, Simonsson
, K.
, Gustafsson
, D.
, and Månsson
, T.
, 2014
, “A Load History Dependent Model for Fatigue Crack Propagation in Inconel 718 Under Hold Time Conditions
,” Eng. Fract. Mech.
, 118
, pp. 17
–30
.18.
Saarimäki
, J.
, Moverare
, J.
, Eriksson
, R.
, and Johansson
, S.
, 2014
, “Influence of Overloads on Dwell Time Fatigue Crack Growth in Inconel 718
,” Mater. Sci. Eng., A
, 612
, pp. 398
–405
.19.
Gutierrez-Urrutia
, I.
, Zaefferer
, S.
, and Raabe
, D.
, 2009
, “Electron Channeling Contrast Imaging of Twins and Dislocations in Twinning-Induced Plasticity Steels Under Controlled Diffraction Conditions in a Scanning Electron Microscope
,” Scr. Mater.
, 61
(7
), pp. 737
–740
.20.
Viskari
, L.
, Cao
, Y.
, Norell
, M.
, Sjöberg
, G.
, and Stiller
, K.
, 2011
, “Grain Boundary Microstructure and Fatigue Crack Growth in Allvac 718Plus Superalloy
,” Mater. Sci. Eng., A
, 528
(6
), pp. 2570
–2580
.21.
Lenets
, Y. N.
, 2012
, “Practical Aspects of Fatigue Crack Growth in Aero-GTE Applications
,” ASME
Paper No. GT2012-68736.22.
Storgärds
, E.
, and Simonsson
, K.
, 2015
, “Crack Length Evaluation for Cyclic and Sustained Loading at High Temperature Using Potential Drop
,” Exp. Mech.
, 55
(3
), pp. 559
–568
.Copyright © 2016 by ASME
You do not currently have access to this content.
