Method for producing nanoheterostructured permanent magnet

A method for producing a nanoheterostructured permanent magnet, comprising:

• a first step of preparing a raw material solution by dissolving, in a solvent,
• a block copolymer comprising at least a first polymer block component and a second polymer block component which are immiscible but linked to each other,
• a first inorganic precursor which is one of a hard magnetic material precursor and a soft magnetic material precursor, and
• a second inorganic precursor which is the other of the hard magnetic material precursor and the soft magnetic material precursor;
• and
• a second step including
• a phase-separation treatment for forming a nanophase-separated structure in which at least a first polymer phase comprising the first polymer block component with the first inorganic precursor introduced thereinto and a second polymer phase comprising the second polymer block component with the second inorganic precursor introduced thereinto are regularly arranged by self-assembly,
• a conversion treatment for converting the hard magnetic material precursor and the soft magnetic material precursor to a hard magnetic material and a soft magnetic material, respectively, and
• a removal treatment for removing the block copolymer from the nanophase-separated structure, to thereby obtain a nanoheterostructured permanent magnet comprising the hard magnetic material and the soft magnetic material.