Abstract
The effects of microstructure and strain amplitude on low cycle fatigue lives and fracture characteristics of Inconel 718 were studied. All the tests were conducted in air at 650°C Results show that the conventional microstructure had only marginally longer fatigue lives than the damage tolerant microstructure irrespective of the applied strain amplitude. The fracture surface and fracture profile observations demonstrate that the resistance to intergranular cracking was improved by the serrated grain boundaries in the damage tolerant microstructure but the concomitant precipitation of large δ along serrated grain boundaries promoted the formation of microvoids and decohesion at the δ plate-matrix interfaces during cyclic straining. The impact of the two microstructures on LCF crack initiation life is also discussed.
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© 1990 Springer Science+Business Media Dordrecht
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Bande, H., Xiao, Y., Au, P., Koul, A.K., Wallace, W. (1990). Low Cycle Fatigue Fracture Behaviour of Conventional and Damage Tolerant Microstructures of Inconel 718 at 650°C. In: Meguid, S.A. (eds) Surface Engineering. Springer, Dordrecht. https://doi.org/10.1007/978-94-009-0773-7_25
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DOI: https://doi.org/10.1007/978-94-009-0773-7_25
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