Effects of Salt Quenching Temperatures on Microstructure and Creep Properties of a PM Ni-based Superalloy

Jun Xie, Sugui Tian, Jiao Liu, Xiaoming Zhou

Beijing Institute of Aeronautical Materials, Beijing 100095, China.
School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, China.
School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870,China.

DOI: 10.4236/msce.2013.11002                

Abstract

By means of the microstructure observation and creep properties measurement, an investigation has been made into the influence of the salt quenching temperatures on the microstructure and creep property of FGH95 superalloy. The results shown that, after full heat treatment, a high volume of g￠ phase and some granular carbide dispersedly precipitate in the matrix. Thereinto, as the molten salt temperature decreases from 650℃to520℃, the size of fine g￠ phase in the alloy decrease gradually and the amount of carbides increase in the alloy. And the alloy quenched in molten salt at520℃possesses better creep resistance due to the fact that there are more granular carbides precipitating in the alloy to enhance the grain strength. During creep, the deformation features of the alloy are that the configurations of stacking fault and slipping dislocations are activated in the alloy.

Keywords

FGH95 Ni-Based Alloy; Salt Quenching Temperature; Microstructure; Creep Property; Deformation Feature

Conflicts of Interest

The authors declare no conflicts of interest.

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