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Title: The Effects of Strain-Annealing on Tuning Permeability and Lowering Losses in Fe-Ni-Based Metal Amorphous Nanocomposites

Here, Fe-Ni-based metal amorphous nanocomposites with a range of compositions (Fe 100–xNi x) 80Nb 4Si 2B 14 (30 ≤ x ≤ 70) are investigated for motor and transformer applications, where it is beneficial to have tunable permeability. It is shown that strain annealing offers an effective method for tuning permeability in these alloys. For an Fe-rich alloy, permeability increased from 4000 to 16,000 with a positive magnetostriction. In a Ni-rich alloy, permeability decreased from 290 to 40 with a negative magnetostriction. Significant elongations (above 60%) are observed during strain annealing at high stress. Crystallization products have been determined in all alloys heated to 480°C. γ-FeNi is formed in all alloys, while (Fe 30Ni 70) 80Nb 4Si 2B 14 also undergoes secondary crystallization at temperatures of approximately 480°C to form a phase with the Cr 23C 6-type structure and a likely composition of Fe 21Nb 2B 6. Toroidal losses have been measured for (Fe 70Ni 30) 80Nb 4Si y B 16–y (0 ≤ y ≤ 3) at various annealing temperatures. At an induction of 1 T and frequency of 400 Hz and 1 kHz, the toroidal losses obtained are W 1.0T, 400 Hz = 0.9 W/kg and W 1.0T, 1 kHzmore » = 2.3 W/kg, respectively. These losses are lower than losses recently reported for state of the art 3.0% and 6.5% silicon steels, a Metglas Fe-based amorphous alloy, and some Fe-based nanocomposites.« less
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  1. Carnegie Mellon Univ., Pittsburgh, PA (United States)
  2. Carnegie Mellon Univ., Pittsburgh, PA (United States); NASA Glenn Research Center, Cleveland, OH (United States); Vantage Partners LLC, Brook Park, OH (United States)
  3. National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States)
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
JOM. Journal of the Minerals, Metals & Materials Society
Additional Journal Information:
Journal Volume: 69; Journal Issue: 11; Journal ID: ISSN 1047-4838
Research Org:
Carnegie Mellon Univ., Pittsburgh, PA (United States)
Sponsoring Org:
Country of Publication:
United States
OSTI Identifier: