Long Time High Temperature Stress Rupture Strength Behavior and Structure Stability Study on Ni-Base Superalloy Nimonic 80A

Abstract:

Nimonic 80A Ni-base superalloy can be used for high temperature steam turbine components.There is a critical requirement for turbine blade application that the stress rupture strength for 105 hrs at relevant high temperatures should be higher than 100MPa.On the other hand, it must keep good structure stability and no harmful phase such as-phase and the TCP phase formation at long time high temperature exposure. Therefore, the long time stress rupture tests at temperatures of 600, 650, 680 and 700°C for different stresses have been carried out. The long time structure stability has been also studied in detail. The results show that Nimonic 80A can meet the critical requirement for USC steam turbine blades at 600~700°C. Any detrimental phases have not been found at the long time stress rupture tests. The morphology of grain boundary carbides also has no apparent change. Based on above mentioned results, Nimonic 80A is recommended to be used for USC steam turbine components in the temperature range of 600~650°C.

• Periodical: Applied Mechanics and Materials (Volume 853)
• Pages: 148-152
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.853.148
• Online since: September 2016
• Authors: Xiao Fei Chen, Zhi Hao Yao*, Mai Cang Zhang, Xi Shan Xie, Qiu Ying Yu, Jing Jing Song, Li Feng Ding, Hong Wei Shen
• Keywords: High Temperature Stress Rupture, Nimonic 80A, Structure Stability

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