Magnetization Process

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Magnet Guide & Tutorial 

 

 

 

 

 

 

  

For more information please contact: 

 

  Alliance LLC 

  1150 Eastport Center Drive                         Phone: [phone] 

  Valparaiso, IN. 46383                                        Fax: [phone] 

  www.Allianceorg.com                                  e-mail: [e-mail] 

 

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Table of Contents 

 

 

Introduction 

    

 

 

2 

History of Magnets 

 

   

 

 

3 

Global Trend for Magnets   

   

 

4 

Magnetic Materials Introduction  

 

5 

Definitions and Terminology 

 

   

6 

Conversions 

  

 

 

  10 

Hysteresis and Demag Curve   

   

11 

Typical Supplier Data Sheets   

 

12 

NdFeB at Various Temperatures 

 

15 

Attributes of Magnet Materials   

 

16 

Highest Properties of Magnets   

 

17 

Manufacturing 

Processes 

   18 

NdFeB and SmCo Manufacturing 

 

19 

Alnico 

Manufacturing 

    20 

Ferrite 

Manufacturing 

    21 

NdFeB Coatings  

  

 

 

 

22 

Adverse Effects on Magnets 

 

 

23 

Magnet 

Assembly     26 

 

Machining 

of 

Magnets 

    27 

Handling 

of 

Magnets 

    28 

Magnetization 

Process    29 

Magnetization 

Types 

    30 

Testing 

Magnets      31 

Initial Design Considerations 

 

 

34 

Selection of Magnet Materials   

 

35 

Things to Include on Your Drawing   

36 

Contact information and References 

37 

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Introduction 

 

 

 

This guide has been developed to provide the fundamental basics of magnetic 

materials, their properties, methods of manufacture, and costing so that the user 

has adequate knowledge when deciding what type or grade of material should be 

used in various applications. 

 

Magnets have enormous importance in the modern world. It would be hard to 

imagine life without their contributions in today’s products. Automobiles have 

several hundred magnets from motor to sensor applications; Consumer 

electronics utilize them to generate video, sound and record; Computers would 

not exist; and the medical field would not have the benefit of MRIs and many high 

RPM instruments used in surgery and dentistry.     

 

The main purpose of magnets is to help in the conversion of energy: 

 

Mechanical to Electrical, such as in generators, sensors and microphones 

Electrical to Mechanical, such as in motors, actuators and loudspeakers 

Mechanical to Mechanical, such as for couplings, bearing and holding devices 

 

With such importance and the complexities of devices utilizing magnets, they are 

a relatively easy material to understand. There are only four major types of 

permanent magnet materials: 

 

NdFeB, Neodymium or Neo Rare Earth 

SmCo, Samarium Cobalt 

SrFe

2

O

3

, Hard Ferrites or Ceramics 

AlNiCo, Alnico magnets 

 

Then, there are only 4 major magnetic performance properties: 

 

Br, Residual Induction. The magnetic flux that remains permanently in a magnet 

Hc and Hci, Coercivity. The Susceptibility for demagnetization of the magnet 

BH 

max

, Energy Product, The total energy stored in a magnet (BrxHc) 

T, Temperature Stability. Reversible, irreversible, max working and Curie temps. 

 

In addition to providing a good understanding of the above characteristics, this 

guide will also provide information related to pricing and availability of all the 

magnetic materials.  

2

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History of Magnetic Materials 

 

 

 

7.0 MGOe 

Sm

2

Co

17

 

SmCo

5

 

NdFeB

50 MGOe

35 MGOe 

30 MGOe 

20 MGOe 

NdFeB

200

°

 C

Ferrites

Alnico 5

KS Steel 

MK Steel 

3.8 MGOe 

6.0 MGOe 

Loadstone 

2.5 MGOe 

<1/2 MGOe 

400 BC 

 

1930           1940           1950           1960           1970             1980        1990          2000

Earliest written reference to magnetism: 

 

"The lodestone makes iron come or it attracts it"  from 400BC China 

 

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