Jet mill

About: Jet mill is a research topic. Over the lifetime, 803 publications have been published within this topic receiving 5686 citations.

Preparation method of sintered samarium-cobalt magnet

Abstract: The invention discloses a preparation method of a sintered samarium-cobalt magnet. The preparation method comprises the following steps: 1 crushing sintered samarium-cobalt alloy ingot to obtain samarium-cobalt alloy particles; 2, feeding the samarium-cobalt alloy particles in jet mill equipment protected by nitrogen, enabling the powder particle to collide with each other under blowing of nitrogen airflow; and adopting a grading wheel to screen the crushed samarium-cobalt alloy powder to remove coarse particles, and then adopting a cyclone separator to remove fine particles through screeningto obtain samarium-cobalt alloy powder with the averaged particle size being 2-10 microns; and 3, carrying out orientation and prepressing forming on the samarium-cobalt alloy powder in a magnetic field, then, carrying out isostatic pressing forming, and finally carrying out sintering forming at 1170-1199 DEG C to obtain the sintered samarium-cobalt magnet. According to the preparation method, thepowder preparation cost is low, the flammable solvent is not used, the potential safety hazard is avoided, the samarium-cobalt alloy powder is excellent in uniformity, the sintered magnet is easy tocontrol, the magnetic property of the product is steadier and better, and the product with various high properties or special property requirements can be prepared.

Pulverizer jet mill

Abstract: A pulverizer for pulverizing solid material such as coal in which the chamber of the pulverizer has jets of fluid projected thereinto at high speed to cause the particles to impact against one another to effect the pulverizing and in which a sleeve is mounted within the pulverizer chamber so that the coarser particles which pass upwardly through the sleeve flow downwardly in the annular space between the sleeve and the chamber side wall, to be re-entrained by the nozzles and projected again into the sleeve for further impacting.

Solid NdFeB magnets made by gas atomization and extrusion.

Abstract: Currently the three methods that are used to make solid NdFeB magnets for commercial production are as follows: (1) Vacuum-induction melt, argon gas atomize to powder, jet mill, magnetically orient, cold press, sinter, and heat treat. (2) Vacuum-induction melt, cast into ingots, rough grind and pulverize, jet mill, magnetically orient, cold press, sinter, and heat treat. (3) Vacuum-induction melt, melt spin to ribbon, pulverize, hot press (MQ2), and hot work (MQ3).

Changes in the structure of talc by continuous jet milling in relation to imposed specific kinetic energy.

Abstract: Ultra fine talc is used in many industries such as paper, paints, polymers, cosmetics and pharmaceutical. Emerging demand with stringent specification from these industries has marked jet mill as one of the essential grinding mill to produce ultra fine talc. Ultra fine grinding testwork of talc was carried out in opposed fluidized bed jet mill by varying the feed rate, classifier rotational speed and grinding pressure at three levels. In this jet mill, grinding and classification took place simultaneously. The ground products were characterized in terms of particle size distribution and mechanochemical effect via X-ray diffraction. The ground product exhibited poly-modal distribution and the minimum size obtained was 4.28 µm at 4 kg/h, 13000 rpm and 4 bar. Besides size reduction in micron range, mechanochemical effect was exhibited by the product ground in jet mill as jet mill is classified as high-energy mill. Reduction in peak intensity and peak base broadening was observed which indicates fine grinding process in jet mill induced mechanochemical effect. Furthermore preferential distortion of (00l) planes was observed as well. The degree of crystallinity of ground sample, which ranged from 26.5% to 85.3% reduces as the specific kinetic energy increase and its reduction gradient varies according to the classifier rotational speed. The crystallite size and lattice strain of talc ranged from 147.69 nm to 353.72 nm and 0.08 to 0.2 respectively.