Microstructure Analysis and Creep Behaviour Modelling of Powder Metallurgy Superalloy

Abstract:

Microstructure analysis of Ni-based superalloy FGH96 under different ageing treatments were carried out in order to understand the microstructure-creep strength relationships of the alloy. It was found that the volume fraction of tertiary γ′ and the mean γ-channel width was significantly varied with different ageing treatments, leading to the changes in creep behavior. The dislocation/γ′ shearing mechanisms were also changed with ageing treatment. The volume fractions of both secondary and tertiary γ′ and the mean γ-channel width were quantitatively analyzed by electron microscopy. The quantified microstructures were used for a crystal plasticity-based constitutive model. It was observed that the crystal plasticity model can accurately simulate experimentally observed creep behavior of aged samples showing significant secondary creep stage.

• Periodical: Materials Science Forum (Volume 913)
• Pages: 134-140
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.913.134
• Online since: February 2018
• Authors: Wen Yong Xu*, Zi Chao Peng, Mu Zi Li, Minh Son Pham
• Keywords: Creep, Powder metallurgy, Superalloy

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