The Effect of Isothermal Deformation Parameters on Abnormal Grain Growth of P/M Nickel-Base Superalloy

Abstract:

The samples with a length of 50mm and cross section area of 20mm2 were machined from extruded P/M Nickel-base superalloy billet and the isothermal deformation tests were carried out at constant strain rate in a vacuum environment using the Thermecmastor. All the samples were deformed to a true strain of 1.04 at deformation temperature 1070°C and 1100°C and strain rate 0.001s-1~1s-1 respectively. The result is the deformation strain rate determine the position and the deformation temperature determine the severity of abnormal grain growth (AGG). The initial grain size and dislocation density is not the only reason to AGG. The AGG is related the recrystallization nucleation process is inhibited in the heat treatment. The AGG region usually has more low energy and low migration rate boundary than other regions.

• Periodical: Applied Mechanics and Materials (Volume 710)
• Pages: 37-43
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.710.37
• Online since: January 2015
• Authors: Shuang Fang*, Min Cong Zhang, Yun Peng Dong, Shu Yun Wang
• Keywords: Abnormal Grain Growth, EBSD, Isothermal Deformation, Ni Based Superalloy

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