Effect of salt-water fog on fatigue crack growth behaviour of 7050 aluminium alloy in different orientations
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The fatigue crack growth behaviour of 7050 T73651 high strength aluminium alloy that was originally developed for the aircraft industry was investigated in this study. The tests were conducted by using C-T specimens machined in six orientations under the action of constant amplitude sinusoidal load cycles. The tests were first carried out in laboratory air and then repeated in salt-water fog of a 5% NaCl solution to observe the effect of the environment on the fatigue crack growth behaviour. The experimental results showed that the fatigue life, maximum stress intensity range and the fatigue crack growth rate of the specimens were seriously affected by the environment. The severity of the effect, on the other hand, was observed to be dependent on the orientation. The strongest orientation was determined to be L-S, while the weakest was S-L.
KeywordsFatigue Aluminium Alloy Stress Intensity Fatigue Life Crack Growth Rate
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- 1.L. F. Mondolfo, in “Al-Alloys Structure and Properties”, (Butterworths, London, 1976), p. 842.Google Scholar
- 2.Report No: TF-621.3, “Materials Research on Specific Components; Studies on Fracture Toughness and Fatigue Behavior of 7050 T73651 Semi-Product”, IABG, West Germany, 1976.Google Scholar
- 3.ASTM E 647-83 (American Society for Testing and Materials, Philadelphia, 1983).Google Scholar
- 4.J. Eftis, L. D. Jones andH. Liebowitz in AGARD-ograph No. 176, “Fracture Mechanics of Aircraft Structures”, 1974, edited by H. Liebowitz, p. 32.Google Scholar
- 5.A. Cigada, B. Mazza, T. Pastore andP. Pedeferri, in Proceedings of an International Conference on HSLA Steels '85, China, November 1985 (ASM, Beijing, 1985).Google Scholar
- 6.M. O. Speidel, “Stress Corrosion and Corrosion Fatigue Crack Growth in Al Alloys”, Paper prepared for NATO ASI on SCC, Copenhagen, July 1975.Google Scholar
- 7.A. Cigada, M. P. D'ambrosio, T. Pastore andP. Pedeferri, in Proceedings of the 5th International Offshore Mechanics and Arctic Eng. Symposium, Vol 2 (ASME, 1986) p. 262.Google Scholar
- 8.D. Aliaga andE. Budillon, in AGARD Conference Proceedings No. 316, “Corrosion Fatigue, Behaviour of Some Aluminium Alloys”, Turkey, April 1982, 3-1.Google Scholar
- 9.D. J. Duquette, in AGARD Conference Proceedings No. 316, “Mechanism of Corrosion Fatigue of Aluminium Alloys”, Turkey, April 1982, 1–1.Google Scholar