Magnetic magnet

Description: The third generation of rare earth permanent magnet NdFeB is the strongest performance of contemporary permanent magnets. Its value is 5-12 times BHmax ferrite magnets, is 3-10 times alnico magnet; it's the equivalent of 5-10 times the coercive force of ferrite magnets, alnico magnet 5 15 times the magnetic potential is extremely high, it can pick up the equivalent of 640 times the weight of its own weight. As the main raw material of iron NdFeB magnets are very cheap, compared with reserves of rare earth neodymium, samarium more than 10-16 times, so the price is much lower than the samarium-cobalt magnets. Mechanical properties of NdFeB magnets are better than samarium cobalt magnets and alnico magnets, easier cutting and drilling and machining complex shapes. Inadequate NdFeB magnets is its poor temperature performance, high temperature magnetic loss is large, the maximum operating temperature is lower. Generally around 80 degrees Celsius, after special treatment magnet, its maximum operating temperature up to 200 degrees Celsius. Because the material contains large amounts of neodymium and iron, it is easy to corrosion is one of its major weaknesses. So NdFeB magnets have the surface coating. Nickel can be electroplated (Ni), zinc (Zn), gold (Au), chromium (Cr), epoxy resin (Epoxy) and the like. [1] The final choice 2014-5-4 16:19:24 Since the magnet can attract iron, so if you can attract other metals it? Our ancestors did a lot of attempts, not only can not find a magnet to attract gold, silver, copper and other metals, can not attract the bricks and the like items. Western Han Dynasty, when it has been recognized that a magnet can attract iron, but not attract other items. When the two magnets together close to each other, and sometimes attract each other, sometimes mutually exclusive. People know that the magnet has two poles, one said N pole, a said S pole. Like poles repel each other, opposite poles attract each other. At the time people do not know the truth, but this phenomenon can still perceived. To the Western Han Dynasty, there was a big alchemist named Luan, he used the nature of the magnet made of two pieces like things, by adjusting the polarity of the mutual position of the two pieces, sometimes two pieces attract each other, sometimes mutually exclusive. Luan big called "fighting chess." He dedicated this novel stuff Han Dynasty, and the spot demonstration. Han Emperor marveled, Dragon Heart big Yue, Feng Luan much actually "five of General Lee." Luan big advantage of the nature of magnets, produced a novel stuff deceived the Han Dynasty. Earth is a big magnet, and its two poles are close to the geographic South Pole and the geographic North Pole. Thus the magnet surface of the earth, when free to rotate, it will same-sex repulsion due to the magnet, an indication of the nature of the opposite sex attraction north and south. The ancients understood this truth is not enough, but this type of phenomenon they are very clear. Category magnets can be grouped into "permanent magnet" and "non-permanent magnets." Permanent magnet may be a natural product, known as lodestone, magnet system can also be made by hand (the strongest magnets are neodymium magnets). The non-permanent magnets, magnetic only under certain conditions there, usually in the form of an electromagnet to produce, i.e. the use of electric current to strengthen the magnetic field. Defined magnets should be called magnet, English: Magnet, Magnet mainly divided into two categories, one is soft, one is hard-magnetic. The concept includes soft core silicon steel and soft; hard magnetic including aluminum, nickel and cobalt, samarium cobalt, ferrite and NdFeB, of which, the most expensive is samarium cobalt magnet, the cheapest is ferrite magnets highest performance NdFeB magnets, but the most stable performance, temperature coefficient is best Alnico, the user can select different hard magnetic products according to different needs. We are talking about magnets, generally refers to the permanent magnets.