Hot-pressed and deformed magnet comprising nonmagnetic alloy and method for manufacturing same

A method for manufacturing an R-TM-B hot-pressed and deformed magnet, the method comprising the steps of:

• (a) preparing a magnetic powder from an R-TM-B alloy, wherein the R-TM-B is Nd30B0.9Co4.1Ga0.5FeBal;
• (b) manufacturing a sintered body by press sintering the magnetic powder;
• and
• (c) hot-pressing and deforming (hot deformation) the sintered body by applying heat and pressure,
• wherein the method further comprises adding and mixing a non-magnetic alloy at a time before the press sintering in Step (b),
• wherein the magnetic powder is a polycrystalline particle including a plurality of crystal grains,
• wherein the polycrystalline particle is a multi domain particle including a plurality of domains,
• wherein an average particle size of the magnetic powder is 100 μm to 500 μm,
• wherein the non-magnetic alloy comprises a Nd-rich phase,
• wherein the non-magnetic alloy further comprises Nd0.84Cu0.16 or Pr0.84Cu0.16,
• wherein the magnetic powder comprises a magnetic powder manufactured by any one process selected from the group consisting of a hydrogenation disproportionation desorption and recombination (HDDR) process, a melt spinning process, a rapid solidification process, and a combination thereof,
• wherein the non-magnetic alloy is added in an amount of 0.5 wt % to 1.5 wt % based on a weight of the magnetic powder,
• wherein Step (b) is carried out at a temperature of 300° C. to 800° C.,
• wherein Step (c) is carried out at a temperature of 500° C. to 1,000° C.,
• wherein the non-magnetic alloy is added before the press sintering in Step (b), and is mixed with the magnetic powder,
• wherein the method further comprises a step of subjecting the sintered body to an additional heat treatment between Steps (b) and (c),
• wherein the additional heat treatment is carried out at a temperature of 400° C. to 800° C., and
• wherein a deformation ratio of the hot-pressing and deformation in Step (c) is 50% to 80%.