Nanostructured Mn-Al Permanent Magnets And Method of Producing Same

A method for producing a bulky nanocrystalline solid comprising

• melting a mixture of metals comprising between 52-58 atomic percent manganese and between 42-48 atomic percent aluminum to form a substantially homogenous solution;
• casting the solution to form ingots;
• measuring compositions of the ingots;
• crushing the ingots to form crushed powders;
• milling the crushed powders to form nanocrystalline powders;
• verifying the presence of τ phase and determining the amount of the τ phase;
• and
• simultaneously consolidating the nanocrystalline powders into a bulky nanocrystalline solid and undergoing phase transformation from ε phase to at least 80% τ phase.

A method for producing a bulky nanocrystalline solid comprising:

• melting a mixture of metals comprising 51 atomic percent manganese, 46 atomic percent aluminum and 3 atomic percent carbon to form a substantially homogenous solution;
• casting the solution to form ingots;
• measuring compositions of the ingots;
• crushing the ingots to form crushed powders;
• milling the crushed powders to form nanocrystalline powders;
• verifying the presence of τ phase and determining the amount of the τ phase;
• and
• simultaneously consolidating the nanocrystalline powders into a bulky nanocrystalline solid and undergoing phase transformation from ε phase to at least 80% τ phase.

A permanent magnet comprising bulky consolidated nano structured manganese aluminum alloy comprising at least about 80% of a magnetic phase and having a macroscopic composition of MnXAlYDoZ, wherein

• Mn is manganese,
• Al is aluminum,
• Do is a dopant,
• X ranges from 5251-58 atomic %, percent,
• Y ranges from 42-48 atomic %, percent, and
• Z ranges from 0 to 3 atomic percent %.