Basically, magnets are elements which can generate a magnetic field which helps to pull a certain material or repel materials like iron and nickel. Magnets are not always made of the same materials and therefore magnets can be categorized based on its composition.
- Temporary Magnets- Temporary magnets are those magnets which have their magnetic properties as long as they are in a magnetic field
- Permanent Magnets- Permanent magnets are those magnets which retain their magnetic properties once they are magnetized and they do not lose their properties even when they are not in a magnetic field.
- Electro Magnets- Electromagnets are those coils of wires who act as a magnet and gain the properties of a magnet when electricity passes through them. The strength of the magnet is altered by the change of direction of the current.
Permanent Magnets can be categorized into four parts:
- Neodymium Iron Boron (NdFeB)
- Samarium cobalt (SmCo)
- Ceramic or Ferrite
Neodymium Iron Boron (NdFeB) – This is a magnet which is made of rare earth materials with high coercive force. Generally, the energy range of the product is very high. Since the energy level is very high therefore they are made in small sizes. So most customer buy custom magnet will choose this material. All the Neodymium Iron Boron magnets have a low mechanical strength and are very much prone to breaking. This is generally used for coating purposes. It is very hard to demagnetize and oxidation a Neodymium Iron Boron. But that is most popular in the market.
Samarium Cobalt (SmCo) – This kind of magnets is also very strong in nature and they cannot be demagnetized very easily. These magnets are resistant to oxidation and temperature and they can bear up to 300 Celsius. There are two series of Samarium Cobalt Sm1Co5 and Sm2Co17. The mechanical strength of these magnets is very low and the magnets are very much expensive.
Alnico– This magnet is made of aluminum, nickel, and cobalt and the name of this magnet is from the first two letters of all the three components. These magnets are very much resistant to temperature and this magnet can also be demagnetized easily. This magnet is produced by the process of casting or by the process of sintering. Both the process helps in creating different properties of the magnet. The process of sintering help in producing more mechanical traits whereas casting helps in increasing the energy of the magnet.
Ceramic or Ferrite– This magnet is generally made with help of iron oxide which is sintered and strontium or barium carbonate. These magnets are generally very cheap and production of the magnets is also very easy. The magnets are generally brittle in nature and so they need to go through the process of grinding with help of a diamond wheel. This magnet is used everywhere they are very strong in nature and it is not easy to demagnetize it.
Temporary magnets are those magnets which show the properties of a permanent magnet when they are in a magnetic field. As soon as they go out of the magnetic field they lose all their magnetic properties. Generally, objects which are made of soft iron like paper clips are temporary magnets.
Electromagnets are generally magnets which are made by the help of winding a wire into multiple numbers of loops around a core material. Electromagnets can never be created without any form of current passing through the coils. The whole setup is called solenoid. In order to magnetize an electromagnet electric current needs to be passed through the whole solenoid setup so that a magnetic field is created. The strength of the magnet depends on the number of loops it has the strength of the field is maximum in the inside of the coil.
The materials that have been used in the center of the electromagnetic coil and the solenoid core are the factors for the strength of the whole electromagnetic field. If the wire is wrapped with wood, then the strength of the electromagnet will decrease and if the wire is wrapped with a Ferro magnet then the strength of the electromagnet is an increase. These are the different types of magnets which are used by people. Most of the magnets are used for industrial purposes and coated on different products to create a magnetic field.