Thermomechanical Process Effects on Hardness and Grain Size in Incoloy® Alloy 908

  • L. S. Toma
  • I. S. Hwang
  • M. M. Steeves
  • R. N. Randall
Part of the An International Cryogenic Materials Conference Publication book series (ACRE, volume 40)


The relationship between thermomechanical processing, hardness, grain size and mechanical properties has been studied for INCOLOY® alloy 908, a nickel-iron base superalloy developed for use as a conduit material in Nb3Sn cable-in-conduit conductors (CICC).1 The alloy has thermal coefficient of expansion properties tailored for Nb3Sn, minimizing compressive strain in the superconductor due to cooldown and the associated reduction in critical properties (upper critical field, critical temperature, and critical current). Alloy 908 also has mechanical properties at cryogenic temperatures that compare favorably with other materials. It is therefore one of the candidate materials for use in the magnets of the International Thermonuclear Experimental Reactor (ITER).2,3


Cold Work Vickers Microhardness Extrusion Ratio International Thermonuclear Experimental Reactor Elongation Ratio 
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Copyright information

© Springer Science+Business Media New York 1994

Authors and Affiliations

  • L. S. Toma
    • 1
  • I. S. Hwang
    • 2
  • M. M. Steeves
    • 1
  • R. N. Randall
    • 1
  1. 1.Plasma Fusion CenterMassachusetts Institute of TechnologyCambridgeUSA
  2. 2.Department of Materials Science and EngineeringMassachusetts Institute of TechnologyCambridgeUSA

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