Helmholtz Free Energy and the Activation Volume of Steady-State Creep in FGH96 Superalloy

Abstract:

The creep properties of FGH96 superalloy were studied in the temperature range of 650 °C to 750 °C and stress range of 690MPa to 897MPa. The results show that the creep life of the alloy decreased significantly with the increase of stress and temperature. However, the temperature produced more effects than that of stress. The most suitable service temperature and stress were also obtained based on the creep results. A physical model base on crystal-plasticity theory was established, but the simplification of the Helmholtz free energy and the activation volume might reduce the accuracy of strain rate prediction. Based on the results of creep at different stresses and temperatures, the Helmholtz free energy and the activation volume of steady-state creep were obtained, which would play a key role in creep life prediction.

• Periodical: Materials Science Forum (Volume 1035)
• Pages: 206-211
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.1035.206
• Online since: June 2021
• Authors: Zi Chao Peng*, Jin Wen Zou, Lei Zhou, Xu Qing Wang
• Keywords: Activation Volume, Creep, FGH96, Helmholtz Free Energy

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