Microstructure and Magnetic Properties of Bulk Nanocrystalline MnAl

Journal Article · Wed Jan 22 00:00:00 EST 2014 · Metals

DOI:https://doi.org/10.3390/met4010020· OSTI ID:1211518

Chaturvedi, A; Yaqub, R; Baker, I

MnAl is a promising rare-earth free permanent magnet for technological use. We have examined the effects of consolidation by back-pressure, assisted equal channel angular extrusion processing on mechanically-milled, gas-atomized Mn-46% at. Al powder. X-ray diffraction showed both that the extruded rod consisted mostly of metastable tau phase, with some of the equilibrium gamma(2) and beta phases, and that it largely retained the as-milled nanostructure. Magnetic measurements show a coercivity of <= 4.4 kOe and a magnetization at 10 kOe of <= 40 emu/g. In addition, extrusions exhibit greater than 95% of the theoretical density. This study opens a new window in the area of bulk MnAl magnets with improved magnetic properties for technological use.

• Sponsoring Organization: USDOE Advanced Research Projects Agency - Energy (ARPA-E)
• DOE Contract Number: DE-AR0000188
• OSTI ID: 1211518
• Journal Information: Metals, Vol. 4, Issue 1; ISSN 2075-4701
• Country of Publication: United States
• Language: English