Low Cycle Fatigue Properties of FGH720Li Superalloy

Abstract:

Low cycle fatigue (LCF) properties of a powder metallurgy(PM) nickel base superalloy FGH720Li were systematically studied in this work, including smooth LCF and notched LCF tested at various temperatures and different stress. The relationship between the fatigue life and applied stress was analyzed both for smooth fatigue and notch fatigue tests. The effects of loading frequency and stress ratio on LCF behavior were also studied. As an important influencing factor of the fatigue life in powder metallurgy superalloy, the effect of inclusions on LCF life was also investigated. The results showed that the fatigue properties of FGH720Li alloy was excellent, when tested at the temperature of 450°C and applied stress of 1230MPa, the fatigue life could exceed 5×10⁴ cycles. When tested at 650°C and 1150MPa, the average fatigue life was still beyond 2×10⁵ cycles.

• Periodical: Materials Science Forum (Volume 1035)
• Pages: 292-296
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.1035.292
• Online since: June 2021
• Authors: Zi Chao Peng*, Jun Ying Sheng, Xu Qing Wang, Yue Tang
• Keywords: FGH720Li, Inclusion, Low Cycle Fatigue (LCF), Powder Metallurgy Nickel Base Superalloy

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