---
title: Intrinsic and Extrinsic Demagnetization Curves
description: Ferromagnetic materials such as iron, cobalt, nickel, and many alloys, including permanent magnets, show a magnetic hysteresis phenomenon.
---

[EEC Blog ](https://blog.electronenergy.com)

# [Intrinsic and Extrinsic Demagnetization Curves](https://blog.electronenergy.com/demagnetization-curves)

 Written by [Electron Energy](https://blog.electronenergy.com/author/electron-energy) | Dec 23, 2020 3:50:12 PM

## What is a demagnetization curve?

Ferromagnetic materials such as iron, cobalt, nickel, and many alloys, including permanent magnets, show a **magnetic hysteresis** phenomenon. The hysteresis loop is generated by measuring the magnetization **M**, while changing the applied external magnetic field **H** (see green curve in the figure to the left).

The magnetization in a ferromagnetic material increases from 0 or ‘virgin’ state (point ⓪ as show in the figure to the left) due to an increasing applied magnetic field, to a maximum--the point where the magnetization does not increase anymore, called magnetic saturation (point ①). Upon reducing the magnetic field back to 0, permanent magnets still retain a high value of magnetization (point ②) also known as **Br**. The magnetization will eventually decrease to 0 (point ③) by applying a magnetic field in the opposite direction. The magnetic saturation in the opposite direction will occur (point ④) with increasing magnetic field in that direction.

## Why is the demagnetization curve important?

Important magnetic properties of permanent magnets, such as residual induction **Br**, coercivity **Hc**, intrinsic coercivity **Hci**, and maximum energy product **(BH)max**, can be obtained from demagnetization curves.

**Br **is the residual induction or flux density, which represents the magnetic induction corresponding to zero magnetizing field in a magnetic material after full saturation when measured in a closed magnetic circuit. The unit for magnetic induction** B** and residual induction **Br** is **G**, Gauss (CGS unit) or **T**, Tesla (SI unit).

**Mr** is the remanent magnetization or remanence, which represents the retained magnetization when the external magnetic field is reduced to zero after full saturation when measured in a closed magnetic circuit.

The unit for magnetization **4πM** and remanent magnetization **4πMr** is **G**, Gauss (CGS unit) or **A/m**, Ampere per meter (SI unit)...

 

[View full post](https://blog.electronenergy.com/demagnetization-curves)

```json
{
  "@context" : "http://schema.org",
  "@type" : "BlogPosting",
  "author" : {
    "@type" : "Person",
    "name" : "Electron Energy"
  },
  "dateModified" : "2020-12-23T15:50:12.675Z",
  "datePublished" : "2020-12-23T15:50:12Z",
  "headline" : "Intrinsic and Extrinsic Demagnetization Curves",
  "image" : {
    "@type" : "ImageObject",
    "height" : 175,
    "url" : "https://f.hubspotusercontent00.net/hubfs/4788906/social.png",
    "width" : 269
  },
  "mainEntityOfPage" : "https://blog.electronenergy.com/demagnetization-curves",
  "publisher" : {
    "@type" : "Organization",
    "logo" : {
      "@type" : "ImageObject",
      "height" : 60,
      "url" : "/hs/hsstatic/content_shared_assets/static-1.4092/img/default-amp-logo.png",
      "width" : 60
    },
    "name" : "EEC Blog"
  }
}
```