Method for manufacturing rare earth magnet

A method for manufacturing a rare earth magnet, comprising a grain boundary diffusion process, the method comprising:

• forming at least one kind of a film selected from an R2 film, an R2-M alloy film, and a multilayer film of R2 and M by a physical vapor phase deposition method, on plural sintered articles each having a first surface and a second surface on an opposite side to the first surface, each comprising an R1—Fe—B based composition;
• and then allowing R2 or R2 and M to be absorbed by the sintered articles through a heat treatment,
• wherein:
• the plural sintered articles are disposed side by side with a jig in such a manner that the first surfaces of the plural sintered articles are along a plane in parallel to a vertical direction or a horizontal direction,
• R2 represents at least one kind of an element selected from rare earth elements, and is required to be one kind or two kinds of Tb and Dy, M represents at least one kind of an element selected from the group consisting of Cu, Al, Co, Fe, Mn, Ni, Sn, and Si, and R1 represents at least one kind of an element selected from rare earth elements, and is required to be one kind or two kinds of Pr and Nd,
• the grain boundary diffusion process comprises:
• a first forming of the film on the first surface of the plural sintered articles disposed side by side with the jig in an inert gas atmosphere, in a first film forming treatment chamber having provided therein a target containing R2 provided by disposing on a side of the first surfaces of the plural sintered articles;
• a second forming of the film on the second surface of the plural sintered articles disposed side by side with the jig in an inert gas atmosphere, without reversing the plural sintered articles, in a second film forming treatment chamber, which is juxtaposed with the first film forming treatment chamber, having provided therein a target containing R2 provided by disposing on a side of the second surfaces of the plural sintered articles;
• and
• a moving of the plural sintered articles disposed side by side with the jig in a horizontal direction or a vertical direction between the first film forming treatment chamber and the second film forming treatment chamber,
• the jig contains at least one kind of a material selected from the group consisting of aluminum, an aluminum alloy, copper, a copper alloy, iron, an iron alloy, titanium, a titanium alloy, niobium, a niobium alloy, tungsten, a tungsten alloy, molybdenum, and a molybdenum alloy;
• the jig has a holding part formed to have points, between which the sintered article is held;
• the jig contains plural lateral frames;
• the sintered article is disposed between the adjacent lateral frames;
• the holding part comprises a beam;
• the beam is elastically deformed in such a manner that one point of the points is moved upward, whereas the other point of the points is moved downward, with the lateral frame as the center;
• the lateral frames can be elastically deformed;
• and
• the points of the holding part each have a moving distance within elastic limit that is twice or more a dimensional tolerance range of a dimension of the sintered article in a holding direction.