• Rafting in single crystal nickel-base superalloys — An overview

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      https://www.ias.ac.in/article/fulltext/sadh/028/01-02/0115-0128

    • Keywords

       

      Single crystal superalloys; rafting; multiaxial stress states; creep; kinetics of rafting; parabolic growth of γ-channel width

    • Abstract

       

      Currently nickel-base single crystal (SX) superalloys are considered for the manufacture of critical components such as turbine blades, vanes etc., for aircraft engines as well as land-based power generation applications. Microstructure and high temperature mechanical properties are the major factors controlling the performance of SX superalloys. Rafting is an important phenomenon in these alloys which occurs during high temperature creep. It is essential to understand the rafting mechanism, and its characteristics on high temperature properties before considering the advanced applications. In this review article, the thermodynamic driving force for rafting with and without stress is explained. The nature and influence of rafting on creep properties including pre-rafted conditions are discussed. In addition, the effect of stress state on γ/γ′ rafting, kinetics and morphological evolution are discussed with the recent experimental results.

    • Author Affiliations

       

      M Kamaraj1

      1. Department of Metallurgical Engineering, Indian Institute of Technology-Madras, Chennai - 600 036, India
    • Dates

       

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