Scientists have long been trying to create ultra-strong magnets based on various alloys. But in most developments it was necessary to use materials that could be dangerous to humans. Finally, it was possible to obtain a composition based on neodymium. This rare earth metal poses no potential health hazard. Having become acquainted with the unique properties of such a material, many wonder whether it is possible to make neodymium magnets with their own hands. According to the idea, this is a technologically complicated process. Or maybe you can do it from recycled recycled materials?
Neodymium magnets: what is this material?
According to scientists, this development took about 20 years of research and testing. When choosing materials, many factors were taken into account: accessibility, manufacturability, safety, high magnetic properties, resistance to environmental conditions. A promising direction, scientists considered the use of rare earth metals. And neodymium for these purposes came up just perfectly.
Magnets based on it have amazing adhesion. Even a small volume of material allows you to maintain weight many times greater than its mass. Magnetic properties persist for a long time (lose no more than 2% for 10 years of use). Now neodymium magnets can be purchased in specialized stores. Prices are available to almost anyone.
Composition
Magnets based on this rare earth metal are denoted by the formula Nd2Fe14B. The composition includes neodymium (Nd), iron (Fe), boron (B). A feature of the technology is that this rare earth metal in its pure form is difficult to isolate. The sintering process with the remaining components in powder form must take place in an inert environment. Otherwise, its rapid oxidation with loss of properties occurs.
The technology for complex conditions is complicated, so trying to make neodymium magnets with your own hands is not practical. Products are labeled during production. The number after the letter N (25, 30, 45) indicates the code. The higher the indicator, the stronger the magnetic properties of the material. The maximum working temperature of the magnet also depends on the number.
Features
To prevent exposure to environmental conditions, the magnets are coated with a protective compound. Usually these are two layers of nickel or an improved version with an intermediate additional layer of copper. Another important feature - neodymium magnets at temperatures above 70 ° C begin to demagnetize. Exceeding the limit values can lead to a complete loss of properties and the transformation of the alloy simply into a piece of metal.
The specificity of the material implies special safety measures during operation. So, neodymium magnets 50x30 mm have a cohesive force of 100 - 115 kg, and 70x50 mm up to 300 kg. In case of careless handling, they can cause harm: pinch fingers, injure skin, damage the bone. In an uncontrolled collision of two magnets, crumbling of the material with the formation of sharp fragments that can injure the eyes is possible.
Application
Traditionally, they are used in electronic devices and devices where it is necessary to create a constant magnetic field. The properties of the material make it possible to successfully apply them when searching for and lifting metal objects from the bottom of water bodies. Such designs, in addition to the eyelets for fastening the cable, are equipped with an eye bolt, which is simply necessary, since when screwing in, it allows you to disconnect two strongly interlocked surfaces.
Magnets are available in sizes from 1 to 120 mm in diameter and of different thicknesses and shapes. The thinnest of them are widely used in the leather and furniture industry. They can be found in funny toys and devices for hanging various utensils. Powerful magnets are indispensable for filtering bulk and liquid materials. They are used to trap metallic impurities and foreign objects in the conveyor stream.
High adhesion forces people to use them to obtain "savings" when using water and gas. By purchasing neodymium magnets for counters, they thus try to stop or slow down the rotation of their mechanism. Such a possibility theoretically exists in devices where steel elements are used inside. A powerful magnet mounted in a specific location on the housing can slow down the rotation of the impeller.
Is it possible to make neodymium magnets with your own hands?
Industrial technology, in addition to sintering the mass into an alloy, involves a more complicated and inaccessible for home conditions magnetization of the obtained substance. For this, very powerful force fields are used. If you have a great desire to get neodymium magnets yourself, you can do it yourself by dismantling the electronics that have "outlived" your age.
In some old hard drives, one or two small elements can be found inside. Trying to drill or crush such magnets is impractical. The surface protective layer is damaged, the material reacts with the medium and loses its properties. In addition, as experts assure, the chip has a high flammability and can ignite the surrounding surfaces.