How The Magnets Are Made

  How the magnets are made

  Iron, cobalt, nickel or ferrite and other ferromagnetic materials are different, its internal electronic spin can be spontaneously arranged in a small range to form a spontaneous magnetic zone, this spontaneous magnetic domain called magnetic domain. Ferromagnetic material magnetization, the internal magnetic field neat, aligned in the same direction, so that the magnetic enhancement, it constitutes a magnet. Magnet magnetization process is the iron block of the magnetization process, magnetized iron and magnets have different attraction between the polarity, iron is firmly with the magnet "sticky" together. Natural magnets are iron oxide and man-made magnets are usually steel. Steel after magnetization will always retain the magnetic general refers to the natural permanent magnet is not just ferrite (iron oxide), as well as iron cobalt nickel alloy, iron rare earth alloy and other permanent magnetic materials, such as aluminum nickel Cobalt, samarium cobalt, neodymium iron boron, these are also very common, very strong magnetic, these substances can be magnetic field magnetic field magnetization, and magnetization itself has a magnetic and does not disappear. The composition of the artificial magnet is based on the magnetization properties of the various metals, and the magnet is close to the magnetic substance, which is sensed to the same end and the other end produces the same name.

  Magnet classification A. Temporal (soft) magnet a. Meaning: magnetic short, when the magnet removed after the magnetic disappeared. B. Example: nails, wrought iron B. permanent (hard) magnets a. Meaning: magnetization, long-term preservation of magnetic. According to the above principle, according to the principle of electromagnetic induction, a strong current can produce a strong magnetic field, the use of strong magnetic field magnetization of ferromagnetic material, and because of different material magnetization characteristics are not the same, some substances Easy to magnetize, and not easy to drop (loss of magnetic), can be a long time to keep the magnetic. The magnetization of this material produces magnets. Use a magnetizer to magnetize the hard magnets.

  According to the principle of electromagnetic induction, the current can produce a magnetic field, the use of strong magnetic field magnetization of hard magnetic material is generally known as the magnet of the magnetic material, in fact, several different things: the most common magnets, such as the general speaker with the magnet, Fog oxygen. They are used in the hot rolling process of steel from the billet rolled off the surface of the iron scale (sheet of iron oxide), after impurity removal, crushing and then add a small amount of other substances, into the steel mold in the compression molding , And then in the reductive furnace (hydrogen) sintering, so that part of the oxide reduction was ferrite, cooling, and then placed in the exciter to produce magnetized. Heavier than they are the magnet: the magnet is the real steel, composed of iron, the main high content of nickel. It is generally smelted with intermediate frequency electric furnace (only 100 kilograms per furnace), casting molding, because some of its plane precision requirements, generally have to use grinding machine grinding. And then magnetized, as a product. All kinds of metering power meter used in this magnet. More advanced magnetic material, is NdFeB type magnetic material.

  They are substances containing rare earth elements neodymium, iron and boron. The production is made of cemented carbide: it is made by milling - mixing - molding - sintering - finishing - magnetizing. This kind of magnetic material has the highest magnetic field strength, the best performance, the most expensive price. Is the defense of military and precision equipment will be used. The electronic rotor is the rotor of the stepper motor. Ah, maglev train is certainly used in this kind of magnetic material. Ferrite permanent magnet materials are: strontium - ferrite permanent magnet material and barium - ferrite permanent magnet material, which has an isotropic and anisotropic points, the speaker magnet commonly used ferrite permanent magnet material ; Metal permanent magnet materials are mainly aluminum and nickel cobalt permanent magnet materials and rare earth permanent magnet materials. Rare earth permanent magnet materials are divided into: SmCo permanent magnet materials and NdFeB permanent magnet materials. Rare earth permanent magnetic materials are made by powder metallurgy process.