CN1071613A - Producing method for metal powder - Google Patents

Abstract

The invention relates to a kind of producing method for metal powder.The inventive method is that metal is put into the melting furnace heat fused; melt-flow is crossed and is fallen into the cooling fluid granule that congeals into behind metallic sieve or the rotary disk again; small metal particles is joined in the vortex pulverizer; under the protection of protective gas such as nitrogen or inert gas, pulverize; the metal dust that obtains pulverizing carries out selection by winnowing by winnowing machine; too thick particle is got back to again in the pulverizer and is pulverized, and the powder that meets the requirements is sent in loading head and the deduster and is collected.Can make metal dusts such as magnesium metal, aluminium, manganese with this method, technology is simple, safe and reliable.

Description

Producing method for metal powder

The invention belongs to metal dust manufacturing technology field.

The method of making metal dust is many, one is mechanical milling method, the general ball mill grinding that adopts, this method grinding efficiency is low, impurity is many, two are metal bath atomizing freezing method, in the patent application as Chinese invention patent communique on May 1st, 1991 disclosed " making the method and apparatus of refining metallic powder " (publication number CN1051002A), introduced a kind of manufacture method and be metal bath by the gas jet atomization, the method that mechanical rotary impact atomizing, cooling medium impact atomizing can be produced the I of powder mean particle sizes and reach 10 microns.The metal dust of Zhi Zaoing is because granularity still bigger (10 microns) is difficult to full of industrial requirement in this way.

The objective of the invention is to provide metal dust granularity little (about 1 micron), the production efficiency height that a kind of production technology is simple, make, the producing method for metal powder that impurity is few.

The objective of the invention is to realize with following technical scheme; metal derby is put into the melting furnace heat fused; metal bath after the fusing flows through screen cloth or rotary disk is split into the granule melt with melt; fall into liquid cooling medium then; granule congeals into; with the small metal particles drying; again the granule metal is added in the vortex grinder of sealing with protective gas and pulverize by the extrusion friction between the metallic particles; again by the winnowing machine selection by winnowing; undesirablely fall back in the vortex grinder again row again than coarse granule and pulverize; Jia Gong metal dust purity height like this, purity can reach 99.4%, and the I of powder size reaches below 1 micron.Adopt the inventive method to pulverize and make powder magnesium metal, aluminium, manganese etc.The invention will be further described below in conjunction with accompanying drawing.

Fig. 1 is a disintegrating process sketch of the present invention.

1-charging aperture among the figure, 2-charging door bucket, 3-vortex pulverizer, the 4-motor, the 5-volution blade, the 6-air blast, the 7-loading head, the 8-deduster, the 9-back hopper, 10-sucks airduct, and 11-discharges airduct.

Metal is after fusing in the smelting furnace; melt falls into liquid cooling medium such as water after flowing through metallic sieve; granule congeals into; small metal particles joins charging hopper (2) through super-dry by charging aperture (1); add simultaneously protective gas; protective gas is nitrogen or inert gas, can prevent that metal dust is subjected to oxidation. Metallic particles enters vortex pulverizer (3) again by charging hopper (2), because motor (4) drives volution blade (5) and rotates, force metallic particles in pulverizer (3), to do eddying motion, the pulverizing of particle is undertaken by extruding, the fricting movement between the metallic particles, so impurity is few, and the efficient height of pulverizing. Pulverized metal dust is pressed against the top. When being air blast (6) work, the winnowing machine selection by winnowing sucking the inner generation of airduct (10) negative pressure formation air stream, it is inner that the metal dust of pulverizing in the vortex pulverizer (3) is sucked airduct (10), pass through then air blast (6), discharge airduct (11), the powder that thickness is different enters respectively loading head (7) and deduster (8), is beneficial to collecting packing. Too thick material falls into inner pulverizing of vortex pulverizer (3) again after back hopper (9) enters charging hopper (2). Can regulate the thickness that metal dust is pulverized by the size of regulating air blast (6) blast, blast is big, and then powder is thick, and blast is little, and then powder is thin, and whole crushing system is except charge door and loading head exports, deduster all is sealing device exporting.

Embodiment: the production of aluminium powder.

Metallic aluminium is molten into melt in melting furnace; make and be molten into liquid aluminium and flow through a metallic screen and fall into the water that to congeal into for particle diameter be the particle of 0.1-5mm; behind the dry moisture content; alumina particles is added from charging aperture (1); add nitrogen simultaneously; crushing process is protected; can prevent blast; locate to allow in the little air access to plant at charging aperture (1); the air that control is entered makes oxygen content account for the 2-8% of vortex pulverizer volume; can make aluminium powder in process of lapping, form a spot of alumina protective layer like this, produce violent oxidation when preventing discharging.After material is filled up in vortex pulverizer (3) lining; starter motor (4); volution blade (5) rotates; make the aluminum shot in the pulverizer push mutually, rub and obtain pulverizing; owing to this grinding mode is not to resemble ball and the next difficult pulverizing of arriving of enclosure wall friction in the ball mill; so the crush efficiency height, impurity is few, has significantly reduced in the ball mill ball and enclosure wall in the course of the work because the impurity that self weares and teares and bring into.In pulverizer, pulverized metal dust is pressed against the top, owing to form vacuum flow in suction airduct (10) lining during air blast (6) work, can make the powder extruded from pulverizer suck air blast and blow into loading head (7) and deduster (8) through discharging airduct (11), too thick material directly back hopper (9) enters charging hopper (2) and pulverizes.The aluminium powder particle diameter that obtains of deduster (8) in loading head (7) can reach about 1 micron like this.

Claims (4)

1, a kind of method of making metal dust; comprise metal derby is put into the melting furnace heat fused; the melt cooling is pulverized; the invention is characterized in after the metal bath that makes in the melting furnace flows through screen cloth or rotary disk and fall into liquid cooling medium; little socks congeal into; then the granule metal is pulverized by the extruding between the metallic particles, friction with the vortex pulverizer that protective gas adds sealing; use the winnowing machine selection by winnowing again, undesirablely fall back in the vortex pulverizer again row again than coarse granule and pulverize.

2, the method for manufacturing metal dust according to claim 1, it is characterized in that sucking airduct (10) generation negative pressure when the winnowing machine selection by winnowing is air blast (6) work, the metal dust of vortex crusher for crushing is sucked airduct (10) lining, pass through air blast (6) then, discharge airduct (11), enter loading head (7) and deduster (8).

3, the method for manufacturing metal dust according to claim 1 and 2 is characterized in that the protective gas in metallic particles adds the vortex pulverizer is nitrogen or inert gas.

4, the method for manufacturing metal dust according to claim 1 and 2 is characterized in that controlling the oxygen amount that enters air at the charging aperture place that adds metallic particles is the 2-8% of vortex pulverizer volume.