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Things to Know about Permanent Magnets Material

The Permanent Magnets Material is made from such objects, which are magnetized by themselves so that they can work permanently. The important material is ferromagnetic, which is commonly used as a stronger tool as compared to other materials.

Such magnets have the properties that they retain their magnetic characteristics even in the absence of other current induced to them. Simply we can say that it doesn't require any electric current.  Magnets contain several types, and one of them is permanent Magnets. For everyday life of example, we can observe the refrigerator on which notes hold by the magnets.

They were first discovered in the 1960s, but now it's getting improved day by day. They are used in several commercial and industrial applications like computers, VCRS, Speakers, etc. Their usage can also be held in automobiles like power windows, and antilock brakes. It can also be used in household electronic devices like dishwashers, washing machines and air conditioners. Several other usages contain time-space machines, robots and space.

History:

The history can be traced back to Greek philosopher Thales in 6 century BC. The progress increase in 20th-century step by step.

Lodestone was first strong magnet discovered; lightning strikes were reasons of its discovery.  The magnetic field produced was low but its resistance to demagnetization was very high.

 How does Permanent Magnet work?

Their work is all related to its atomic structure. Different electrons are surrounded by nuclei of its atom, each magnets has its own North and south poles. For making of it the ferromagnetic material is heated on the very high temperature with the external magnetic field, which caused the magnetic domain into its own direction point where it should be aligned. The heated material is then supposed to be cool and the specific aligned domains are locked. At the end the external magnetic field will be removed and the hard magnetic field will be kept aligned to make it stronger and permanent.

Physical properties:

Mostly Permanent Magnets are fragile in nature and can't be used as structural components. Their dimensions and tolerance level depends on the manufacturer but most of them consists tolerance level of +/-0.1 mm.

They can be made into different shapes like rings, bars, disc plus shapes.

Why you need them?

There are several reasons why anyone would be interested for using such magnets. Some main reasons are energy conservation, low cost, convince.

If a company needs some outer power source, it eventually means that they will use their company's money for it. However, if they have such magnets with strong characteristics, they don't need any external power, then of course it can reduce the company's cost.

If a company is using some other materials then they will need their constant maintenance of it. But if they are using stronger permanent magnet then it will not consume the company time.

 Types:

1) Neodymium Iron Boron: 

They are the most commonly used material and considered as the best type because their magnetic strength is very strong which is not easy to demagnetize and get rust with time.

2) Alnico: 

It is the best option for those companies who involve in the production of precise instruments. Alnico magnets don’t require any surface treatment and can remain stable function while work at high temperatures.

3) Samarium Cobalt:

They are brittle but have a higher temperature resistance than neodymium magnets, which are widely used in motors, generators, and wind power.

4) Ceramic

They have advantage of high temperature resistance and low cost which is widely used in the products that require high frequency weak current.

 Manufacturing:

1) The mixture of neodymium, iron and boron is used for manufacturing of it.

2) Sometimes copper, aluminum, nickel and cobalt  are also used.

3) The alloy of samarium and cobalt is also used.

Its measurements will be checked firstly in order to check properties.  Energy stored within a magnet is checked through mega gauss Oersteds.

The other characteristic is the maximum heat the magnet can take without being demagnetize. It is the point where the magnet will completely lose its field.

To check its strong bond maximum heat is given to it of it loss it's point domain it means that the magnet is not permanent.

Costs:

The cost of such strong and hard magnets is high as the raw materials used for it is not cheap like iron dioxide and Sa- carbonate.

Temperature:

The temperature varies for different types of magnets. Curie point refers to the temperature above which a ferromagnetic substance loses its ferromagnetism and becomes paramagnet.

Sometimes it is possible that such strong magnets lose its magnetism according to the theory. Below are 3 common reasons.

1) Heat:  if temperature is given above the certain point called Curie point to ferromagnetic then the magnet will lose their magnetism. The energy at that time given to the structure of strong magnet will completely demolish the structure of that domain. In order to restore the magnetism, the magnet have to be magnetized again.

2) Demagnetize magnetic field: When magnets stayed in an opposing magnetic field, The magnetic domain structure with the same direction inside the magnet will be disturbed, so that the magnetic force becomes smaller or disappears.

 

 3) Shock: this problem occurred in older times when some external sudden shocks were given to magnet then it becomes the cause of losing its magnetic force. But as the technology is getting improved day by day that's why such problem occurs in rare.

 

Conclusion:

The crux of the entire theory is that Permanent Magnet materials are strong enough by itself that it doesn’t need any external power to it. It has some unique properties in it. Such properties of magnet are called remanence and coercivity.

Remanence is residual magnetism after the permanent magnet is magnetized to technical saturation and the external magnetic field is removed. Whereas coercivity is reverse magnetic field intensity that can just reduce the remanence technical saturation to zero.

 

They are very useful especially for industrial applications in order to generate power to it. It is needed to turn mechanical motion into energy to run turbines. In absence of such magnets, we would not be able to get such huge advantages of electricity in such modern devices.

The good strong magnet should be able to produce a high magnetic field but with a low mass and should remain consistence with different influences so that they can't be demagnetized.

 

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