Nanostructured Mn-Al permanent magnets and methods of producing same

摘要

Nanostructured Mn—Al, Mn—Al—C permanent magnets are disclosed. The magnets have high coercivities (about 4.8 kOe and 5.2 kOe) and high magnetization values. An intennetallic composition includes a ternary transition metal modified manganese aluminum alloy Mn—Al—Fe, Mn—Al—Ni, or Mn—Al—Co having at least about 80% of a magnetic τ phase and permanent magnetic properties. The alloy may have a saturation magnetization value of at least 96 emu/g with approximately 5% ternary transition metal replacing Al. The alloy may also have a saturation magnetization value of at least 105 emu/g with 10% ternary transition metal replacing Al.

主权项

1. An intermetallic composition comprising a ternary transition metal modified manganese aluminum alloy comprising a bulk nanostructured alloy with at least about 80% of a magnetic τ phase and having permanent magnetic properties,
the bulk alloy having a macroscopic composition of MnXAlYTZ, wherein T is a ternary transition metal selected from a group consisting of iron, cobalt and nickel, X ranges from 50 atomic % to 60 atomic %, X +Y +Z =100 atomic %, and Z is an amount less than 10 atomic % sufficient to impart a saturation magnetization of at least 96 emu/g and the τ phase comprises Mn, Al and a ternary transition metal selected from the group consisting of iron, cobalt and nickel.