Powder distribution device, powder distribution method of powder distribution device and manufacturing method of NdFeB thin-sheet magnet

Abstract

The invention provides a powder distribution device, which comprises a powder distributor and a mold used in cooperation with the powder distributor, wherein the powder distributor comprises a bottomplate, a side wall connected with the bottom plate and used for forming a containing cavity with the bottom plate, a powder sweeping plate, at least two funnels in butt joint with the side, deviatingfrom the containing cavity, of the bottom plate, and powder distribution valves arranged between the inlets of the funnels and through holes corresponding to the funnels and capable of being opened and closed, through holes which are uniformly distributed and penetrate through the bottom plate are formed in the bottom plate, the powder distributor further comprises weighing devices which are in one-to-one correspondence with the funnels, and the mold comprises a mold body with a containing space and a partition plate dividing the containing space into at least two mold cavities. The powder distribution method comprises the procedures of powder weighing, powder pouring, powder distribution and mold closing. According to the powder distribution device, powder agglomeration can be reduced; and the weighing device is arranged, so that the weight value of the powder filled in each mold cavity can be accurately controlled, and the filling amount of the powder in each mold cavity is consistent so as to realize batch uniform filling and powder distribution of the magnets.

Description

【Technical field】 [0001] The invention relates to the technical field of near-net-shape processing of magnets, in particular to a powder distributing device and a powder distributing method thereof, and a manufacturing method of NdFeB-based thin sheet magnets. 【Background technique】 [0002] With the improvement of people's demand for product performance and experience, acoustic components are developing towards smaller volume, higher energy density, and more complex structures. Near-net molding has become an important direction for the preparation of high-performance sintered NdFeB (NdFeB) magnets. At this stage, the method of preparing magnets is through orientation molding-cold isostatic pressing-sintering-mechanical cutting to obtain magnetic steel sheets with a thickness of about 1mm. [0003] In the prior art, although the cold isostatic pressing has been cancelled, the method of using the mold filling powder molding method to prepare a 6mm thick magnetic steel under t...

AI Technical Summary

Problems solved by technology

However, for the near-net shape of smaller thin magnets, due to the small cavity width and the large relative contact friction area between the powder and the cavity, the friction between the powder and the cavity and the agglomeration of the powder make the powder difficult to form. Evenly distributed in each cavity of the mold

The gaps caused by the agglomeration of powder in the cavity make the distribution of powder in various positions in the cavity inconsistent. After pressing, the internal stress of different positions of the magnet is different, causing the size of the blank and the green body to be uneven, and the performance is also unstable. It is difficult to achieve mass production.

Moreover, for thinner and smaller magnets with a total powder distribution of only a few grams, it is still a huge challenge to achieve a quality error of powder distribution between the cavities of the same mold as low as 1%.

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