Atomization adding device and atomization adding method for neodymium iron boron magnetic powder mixture additive

Abstract

The invention provides an atomization adding device and an atomization adding method for a neodymium iron boron magnetic powder mixing additive. Specifically, the atomization adding device for the neodymium iron boron magnetic powder mixing additive comprises a storage barrel, a weighing barrel, a control system, a connecting rod, a blocking piece and a powder container, wherein the storage barreland the weighing barrel are in flexible connection, the weighing barrel is connected with the control system through a weighing sensor, the weighing barrel and the powder container are connected through the connecting rod, and the blocking piece is arranged at an opening of the powder container, and the connecting rod penetrates through the blocking piece to extend into the powder container. Whenthe atomization adding device for the neodymium iron boron magnetic powder mixing additive is used for adding, the adding device is not in direct contact with the powder, and the air replacement process of the connecting part is introduced, so that oxidation caused by contact of oxygen and the powder in the additive adding process of neodymium iron boron powder and caking and blocking of the powder at an adding opening can be effectively avoided; and therefore, the use, cleaning and maintenance are simple; And meanwhile, atomized additive liquid drops are directly sprayed to the powder duringaddition and cannot be sprayed to the inner wall of the container to cause caking of the powder on the wall of the tank, so that the accuracy of the additive addition amount and the mixing uniformityare improved.

Description

technical field [0001] The invention relates to the technical field of sintered NdFeB processing, in particular to an atomization adding device and an adding method for NdFeB magnetic powder mixing additives. Background technique [0002] The new permanent magnet NdFeB magnet is the third-generation rare earth material that appeared in 1983. It has excellent magnetic properties and relatively low price. In recent years, it has attracted much attention in the fields of energy conservation and environmental protection, new energy, automobiles, and robots. At present, the general process flow of sintered NdFeB magnets is: thin strip (SC flakes)→hydrogen crushing→powder making→magnetic field forming→(isostatic pressing)→vacuum sintering→heat treatment, and the pulverizing process includes pre-powdering Mixing, milling, and mixing after milling. Additives will be added during the mixing process. The additives are mainly ester compounds. The uniformity of the mixing process in the...

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Problems solved by technology

[0003] 1) Mixing before milling, generally adding antioxidants (grinding aids), the purpose is to improve milling efficiency, the main mechanism of action: improve particle fluidity, prevent the formation of secondary particles, and at the same time, the surface energy of the material surface is reduced after adsorption, which can Accelerate the crack growth and improve the grindability of the material; the current method of adding the additive is generally to pour the additive into the ball valve at the opening of the powder container with a funnel. This method has the following disadvantages: ①Open the ball valve when adding, and a small part of the air will Oxidation caused by contact with powder is not conducive to performance improvement; ②After adding, the additives are relatively concentrated and need a long time to mix; ③During the mixing process, the powder stored at the adding port of the ball valve combines with the additives to harden and agglomerate, which is easy to block and difficult clean up;

The above methods of adding lubricant in the mixing process are generally added through the opening of the powder tank or the main body of the mixer, which also has the disadvantages mentioned in the mixing before powder making ①②③

[0005] The patent with the publication number of CN 108480648A opens a hole in the side wall of the powder receiving tank and uses a fluid pump to transport the material while atomizing and adding additives. Contact, easy to block the powder and inconvenient to clean, and the opening increases the risk of powder oxidation from the air leakage of the powder tank; the patent with the publication number of CN 209174907 U adopts a scheme similar to the patent CN 108480648A on the side wall above the material tank to pulse air flow The way to replace the flow pump also has the above-mentioned problems of pollution and port plugging in the mixing process; the patent with the publication number of CN 202367198U sets a boxed tooling above the powder tank and opens 10-200 micropores on the bottom plate to add anti-corrosion. Oxidant, because the amount of antioxidant added is very small, and this kind of tooling has a large bottom plate area, and there are many antioxidant residues, the additive may flow to the tank wall during the addition process, and the powder will adhere to the container wall during the mixing process and is not easy Falling off will inevitably affect the actual amount of additives added and the uniformity of mixing; the patent of Aike Science and Technology Publication No. CN 104399995 A mentions a method of opening an additive port in the jet mill feeding port channel and using high-pressure gas atomization to add the feeding channel Add additives in the form of additives, because the actual ratio of additives is very low, the actual flow control is difficult, and the way of adding intermittently is generally used, and the nozzles in the powder channel are easy to block, and the use of high-pressure gas has potential safety hazards

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