Permanent magnets are made from solid materials that is capable of producing consistent magnetic field. On the other hand, the exerted magnetic field of an electromagnet is produced by electric current flow. Electromagnets are produced using copper wire to form a solenoid.
There are different types of permanent magnets. Each permanent magnet is composed of different characteristics and materials.
- Rare Magnets. These are the strongest magnets and made from neodymium alloy, iron, and boron.
- Samarium Cobalt Magnets. These are made from cobalt, samarium, and small copper, iron, and other materials.
- Ceramic Magnets. This magnet is made from iron oxide and compound of ceramic materials.
- AlNiCo Magnets. It is composed of flexible rubber, nickel, cobalt, and aluminum.
Neodymium magnet is a commonly used and a member of rare earth magnets. Rare magnets are called by its name because they are a rare earth element in the periodic table.
Neodymium is considered as the strongest magnet in the world.
These are the surfaces in which the magnetism leaves and reconnect on return to the magnet. The magnetic poles are facing south and north. The magnetic poles are the area with greatest magnetic field strength.
The simplest way to identify a magnet’s pole is to use a digital or analogue pole identifier or a compass.
The “N” in the neodymium magnets refers to the its different commercially available grade. It is typically the magnet’s strength measure or maximum energy product. There are different neodymium magnet grades ranging from N35 up to N55. As an example, the N35 neodymium magnet grade means that its maximum energy product s 35MGOe. The higher the grade means the magnet is stronger.
There are different types of magnet processing such as the following:
- Casting
- Pressing
- Sintering
- Compression bonding
- Injection molding
- Extruding
- Calendaring
The typical magnet tolerance is +/-0.1mm or 0.004”.
Different Materials that are strongly attracted by a magnet includes the following:
- Iron
- Nickel
- Cobalt
- Steel
No. Magnetic Fields can only be redirected, not blocked or shielded. The magnetic field can be redirected by using ferromagnetic materials such as nickel, cobalt, iron, and more.
When kept in its optimum working conditions, a neodymium magnet is estimated to last for over 100 years.
The following are the different factors that can reduce a magnet’s performance:
- Steel thickness
- Air gap
- Material
- Temperature
- Sheer force