What are Ferromagnetic Materials – Types & Their Applications

Ferromagnetic materials or substances are invented by a French physicist Louis Eugene Felix Neel. He was born on 22^nd November 1904 in Lyon & died on 17^th November 2000 Brive-la-Gaillarde. He studied at Strasbourg University &  got a Nobel prize in physics.  There are several ferromagnetic material manufacturing companies available like Dexter Magnetic Technologies founded in 1951 in Elk Grove Village, Digi Key Electronics founded in 1972 in Thief River Falls, RS components founded in 1937 in Corby by Waring and P.M.Sebestyen, Star Trace Private Limited established in 1985 in Tamilnadu, Shields Company Magnetics in Culver city, Magnum Magnetics Corporation in Marietta, Alliance LLC, Arnold Magnetic Technologies, International Magna Products, Master Magnetics are some of the top magnetic manufacturers.

What are the Ferromagnetic Materials?

In some materials, the permanent atomic magnetic moments have a strong tendency to align themselves even without any external field. These materials are said to be ferromagnetic materials. Some of the examples of ferromagnetic materials are cobalt, iron, nickel, gadolinium, dysprosium, permalloy, awaruite, wairakite, magnetite, etc. There are many ferromagnetic materials, some of the ferromagnetic materials lists is shown in the below table.

  1). Cobalt: The Cobalt is invented by Georg Brandt in 1739. He was born on 26^th June 1964 in Riddarhyttan and died in Stockholm on 29^th April 1768. It is one type of ferromagnetic material found in the earth’s crust. It is represented by a symbol CO in the periodic table and its atomic number is 27.

  2). Iron: An iron is the one type of chemical element which is found in the earth’s crust and it is generally represented by a symbol Fe. The color of iron is silvery grey and the atomic number is 26 in the periodic table. The first electric iron is invented in 1882 by Henry W Seeley, which is used to iron the clothes. The Henry W Seeley born on 20^th May 1861 in Newyork and died on 20^th May 1943.

  3). Nickel: The chemical element nickel is also found in the earth’s crust and it is represented by a symbol Ni. The atomic number of nickels is 28 in the periodic table and the color of nickel is silvery white. This metal is invented by Axel Fredrik Crostedt, he was born in Sweden on 23^rd December 1722 and died on 20^th May 1943.

  4). Neodymium Magnet: It is one type of strong and permanent magnet but it is found in the earth crust rarely and the color of neodymium is silvery white. It is also called as NIB or Neo or NdFeB magnet and the formula of neodymium magnet is Nd₂Fe₁₄B. This metal is invented by Carl Auer Von Welsbach, he was born in Austria on 1^st September 1858 and died on 4^th August 1929.

  5). Chromium dioxide: The chemical formula of chromium dioxide is CrO₂, it is insoluble in water and it is also called as Chromium (iv) oxide. The other names of Chromium dioxide are Carolyn and magtrieve. The metal chromium is discovered by Louis Nicolas Vauquelin, he was born in Austria on 16^th May 1763 and died on 14^th November 1829 in France.

  6). Gadolinium: The Gadolinium is one type of chemical element, which is represented by a symbol Gd. The atomic number of gadolinium is 64 in the periodic table. The metal gadolinium is invented by Paul-Emile Lecoq de Boisbaudran (18^th April 1838 – 28 May 1912) in France and Jean Charles Galissard de Marignac (24^th April 1817 – 15^th April 1894) in Switzerland.

  7). Terbium: The Terbium is also one type of chemical element, which is represented by a symbol Td. It is invented by Carl Gustaf Mosander in 1843 and it is found in earth crust rarely. This chemical element is invented by Carl Gustaf Mosander in 1843. He was born on 10^th September 1797in Kalmar and died on 15^th October 1858 in Stockholm County.

  8). Dysprosium: The Dysprosium is one type of ferromagnetic material, which is identified by Paul Emile Lecoq de Boisbaudran in 1886. He was born on 18^th April 1838 and died on 28^th May 1912 in France. The atomic number of gadolinium is 66 in the periodic table.

Types of Ferromagnetic Materials

There are two types of ferromagnetic materials they are un-magnetized ferromagnetic material and magnetized ferromagnetic material. The classification of ferromagnetic material is shown in the below figure

 1). Un-magnetized Ferromagnetic Material

In every un-magnetized ferromagnetic material, the atoms form domains inside the material. The different domains have different directions of the magnetic moment. Hence the material remains un-magnetized. The un-magnetized ferromagnetic material shown in the below figure

 2). Magnetized Ferromagnetic Material

By applying an external magnetic field to the domains of un-magnetized ferromagnetic, the domains will rotate and aligns in the direction of the magnetic field, because of the domain character of ferromagnetic material even if a small magnetic field is applied gives rise to large magnetization. The magnetic field is much larger than the magnetic field in such material. The magnetic moments of domains are parallel to the magnetic field in ferromagnetism because these domains are also aligning in the same direction.

This is the explanation of the un-magnetized ferromagnetic material and magnetized ferromagnetic material with the diagrams.

Properties of Ferromagnetic Materials

The properties of ferromagnetic material are

• The ferromagnetic substances are strongly attracted by the magnetic field
• These substances show the permanent magnetism even in the absence of magnetic field
• The ferromagnetic substances changes to paramagnetic when the substances are heated at high temperature.

Reason: This is due to the randomization of domains on heating

• All the domains are aligned in a parallel direction

Advantages

The advantages of Ferromagnetic materials are

• Resistance is high
• Cheap
• Hysteresis loss is low
• Electrical resistivity is high,
• Coercivity is low
• High permeability.
• It can operate up to 300⁰ C temperature
• Stability of ferromagnetic materials are good

Disadvantages

The main disadvantage of Ferromagnetic materials is

• Generates week magnetic field

Applications

The applications of the ferromagnetic materials are

• Transformers
• Electromagnets
• Magnetic tape recording
• Hard drives
• Generators
• Telephones
• Loudspeakers
• Electric motors
• Hard disk
• Magnetic Storage

This article describes the list of Ferromagnetic Materials and the explanation of each material, applications, advantages, and disadvantages. Here is a question for you which is the best ferromagnetic material and why?