Rolled Steel Scales Production Of Magnetic Materials With Iron

Iron powder is valuable and important as a basic raw materials for industry. Therefore an investigation has been finished on comprehensive utilization of solid second resources containing iron in Pangang. Aimed at metal magnetism material field, iron powder has been developed successfully by choosing iron scale of steel rolling as main raw material. The present paper has studied the process of purifying, technical parameters of reduced process and relationship between characters of iron powder and that of magnet components.Chemical composition, physical characters, mineral phase constitutes of second resources containing iron are analysed systematically. Results show the physical and chemical performance indexes of iron scale in the steel rolling process are stable and suitable to manufacture iron powder used for magnetism, and its main mineral phase is Fe₂O₃ ,FeO and a little amount of impurity. The contents of Fe₂O₃ is in the ranges of 86%～90%.The compound of Si, Al, Mn, P will come into the terminal products after reduction. Furthermore process performance, Compressibility and magnetic character of components are decreased. Besides the abrasion of molding tool is increased. So the technical route of magnetic seperation and chemical purification is effectively used to decrease the contents of compound with Si, Al, Mn, P, especially to make the content of SiO₂ decline down to 0.1%.Technique terms of primary reduction are found. Under following conditions the content of iron in sponge iron powder can reach 97.5%. reduction temperature in the ranges of 1120°C～ 1140 ℃,reduction time in the ranges of 36 h ～ 44 h.In the experiment of lab technique terms during secondary reduction of sponge iron powder are found and they are following: reduction temperature in the ranges of 850℃～1000 ℃, reduction time in the ranges of 1.5 h 2.5h.Technical parameters are following in the process of manufacturing iron powder with rust of steel rolling. First sponge iron powder is prepared to attain the technical request of magnetism. Second it is necessary to mix all the sponge iron powder. The other parameters are to push 4.5～6Kg powder every boat per eight minutes, gas discharge is 20m³ per hour, reduction temperature is 890℃.Typical chemical composition of the iron powder is TFe 99.27, C 0.009, Si 0.041, Mn 0.32, P 0.013, S 0.006, apparent density in the ranges of 2.6～2.85 g/cm³, particle size below 100 mesh. So the product quality of the iron powder is better than that of the Chinese National standard GB/T4136-94.In the paper effects of properties of iron powder, such as TFe, insoluble substance in hydrochloride acid, particle shape and distribution, compact density, on magnetic properties are studied systematically. As a result it is necessary to increase purity and compact density, to improve the micro shape of powder so as to obtain higher inductance value and suitable Q value.Applying results of manufacturing magnet components with the iron powder show electrical characteristics can reach inductance value 96uH and Q value 1.5 under frequency 10KHz. Therefore all properties of iron powder, including chemical composition, physical properties, process performance, can meet the technical demands of our clients.Results show that the research is promising and beneficial to environmental protection and economic profit.