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A new high-strength spinodal alloy

Published online by Cambridge University Press:  01 April 2005

James A. Hanna ,
Ian Baker ,
Markus W. Wittmann  and
Paul R. Munroe
James A. Hanna*
Affiliation:
Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755
Ian Baker
Affiliation:
Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755
Markus W. Wittmann
Affiliation:
Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755
Paul R. Munroe
Affiliation:
Electron Microscope Unit, University of New South Wales, Sydney, NSW 2052, Australia
*
a) Address all correspondence to this author. e-mail: [email protected]
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Abstract

Preliminary investigations of a new high-strength alloy of composition Fe30Ni20Mn25Al25 (at.%) are described in this paper. The as-cast alloy consisted of a periodic two-phase microstructure of interconnected, ∼50-nm-wide rods with fully coherent {100} interfaces, strongly suggestive of formation by a B2 to [(B2 + body-centered cubic (bcc)] spinodal decomposition. The (Ni,Al)-rich B2 and (Fe,Mn)-rich bcc phases differed in lattice parameter by <0.5%. Hardness and yield strength of the as-cast alloy were found to be approximately 500 VPN and 1500 MPa, respectively, and increased by more than 50% after annealing at 550 °C for several days. (Fe,Mn)-rich precipitates with a β–Mn structure were observed in the annealed material.

Keywords

Intermetallic alloysMechanical propertiesNanoscale
Type
Rapid Communication
Information
Journal of Materials Research , Volume 20 , Issue 4 , April 2005 , pp. 791 - 795
Copyright
Copyright © Materials Research Society 2005

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References

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