Investigation on Work Hardening Behavior of Nickel-Base Superalloy during Hot Working Process by EBSD

Abstract:

The Nickel-base superalloy samples were prepared by the isothermal forging in strain rate 1s^-1 at deformation temperature 1070°C with different strain levels. The EBSD was carried out in order to investigate the microstructural changes that took place due to strain level. The result is the samples has no apparent dynamic recrystallization behavior in hot deformation in 1s^-1 at 1070°C. The true stress-true strain curve has two peak values in the strain level of 20% and 60%, and one valley value in the strain level of 50%. The first peak value is result in the activation of slip system and the beginning of recrystallization and the second peak value of the true stress-true strain curve is result in the inhibition of activation of slip system and grain growth by the dislocation density. The work hardening behavior of P/M Nickel-base superalloy may be related to the size ratio of γ’ phase with grain size.

• Periodical: Advanced Materials Research (Volume 1077)
• Pages: 50-55
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1077.50
• Online since: December 2014
• Authors: Shuang Fang*, Min Cong Zhang, Qiu Ying Yu, Shu Yun Wang, Chun Xiao Cao
• Keywords: EBSD, Hot Deformation, P/M Nickel-Base Superalloy, Work Hardening Behavior

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