Lecture

Permanent Magnets: Hysteresis Cycle

Graph Chat

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.

In course

MICRO-313: Actuators and Electromagnetic systems I

Le cours aborde les principales méthodes pour l'analyse de systèmes électromécaniques. Une étude des grandeurs physiques magnétiques est suivie par la conversion de l'énergie électrique en énergie mécanique. L'aimant permanent est étudié de manière macrosc ...

Description

This lecture explains the hysteresis cycle of permanent magnets, analyzing how it depends on external magnetic fields. It covers the types of magnets available in the market, focusing on induction remanence and coercive field. The lecture also discusses the sensitivity of permanent magnets to temperature, especially neodymium-iron-boron magnets.

In MOOC

Electromechanical conversion I

Electric motors and actuators in general are part of our everyday lives, and can be found in both industrial and consumer applications: automobiles, household appliances, computers and even cell phones use electromechanical systems to create force or motion. This course covers the basic principles involved in the calculation, simulation and design of electromechanical systems such as actuators and electric motors. The course includes the following modules:

Magnetic circuits
Magnetic materials
Si

Instructors (2)

Christian Köchli

Teaching & PhD PhD Students Maël Dagon Past EPFL PhD Students as codirector Sebastiano Merzaghi, Chafic Abu Antoun, Florian Louis Copt, Sofia Lydia Ntella Courses Actuators and Electromagnetic systems I MICRO-313 The course covers the main methods for the analysis of electromechanical systems. A study of magnetic physical quantities is followed by the conversion of electrical energy into mechanical energy. The permanent magnet is studied macroscopically. The dynamic aspect of the system is

Yves Perriard

Yves Perriard was born in Lausanne in 1965. He received the M. Sc. in Microengineering from the Swiss Federal Institute of Technology - Lausanne (EPFL) in 1989 and the Ph D. degree in 1992. Co-founder of Micro-Beam SA, he was CEO of this company involved in high precision electric drive. Senior lecturer from 1998 and professor since 2003, he is currently director of Laboratory of Integrated Actuators. His research interests are in the field of new actuator design and associated electronic devices. In 2009, he is appointed Vice-Director of the Microengineering Institute in Neuchâtel until 2011. In 2013 the Federal Council has named him the the CTI commission in Bern. In 2014 he is appointed guest professor at Zhejiang University in China. In 2017, the lab is granted by the Werner Siemens Foundation of an amount of 12 millions CHF in order to set up a new Center for Artificial Muscules. Since 2018, he is Expert with Innosuisse, the new Swiss Innovation Agency. http://scholar.google.com/citations?hl=fr&user=V2onuO8AAAAJ https://actu.epfl.ch/news/a-12-million-franc-donation-to-create-a-center-for/

Official source

Quiz

Ontological neighbourhood

Physics

Condensed matter physics: Phase transitions

Related concepts (32)

Magnetic moment

In electromagnetism, the magnetic moment is the magnetic strength and orientation of a magnet or other object that produces a magnetic field. Examples of objects that have magnetic moments include loops of electric current (such as electromagnets), permanent magnets, elementary particles (such as electrons), composite particles (such as protons and neutrons), various molecules, and many astronomical objects (such as many planets, some moons, stars, etc).

Coercivity

Coercivity, also called the magnetic coercivity, coercive field or coercive force, is a measure of the ability of a ferromagnetic material to withstand an external magnetic field without becoming demagnetized. Coercivity is usually measured in oersted or ampere/meter units and is denoted HC. An analogous property in electrical engineering and materials science, electric coercivity, is the ability of a ferroelectric material to withstand an external electric field without becoming depolarized.

Saturation (magnetic)

Seen in some magnetic materials, saturation is the state reached when an increase in applied external magnetic field H cannot increase the magnetization of the material further, so the total magnetic flux density B more or less levels off. (Though, magnetization continues to increase very slowly with the field due to paramagnetism.) Saturation is a characteristic of ferromagnetic and ferrimagnetic materials, such as iron, nickel, cobalt and their alloys. Different ferromagnetic materials have different saturation levels.

Ferrite (magnet)

A ferrite is a ceramic material made by mixing and firing iron(III) oxide (, rust) with one or more additional metallic elements, such as strontium, barium, manganese, nickel, and zinc. They are ferrimagnetic, meaning they are attracted by magnetic fields and can be magnetized to become permanent magnets. Unlike other ferromagnetic materials, most ferrites are not electrically conductive, making them useful in applications like magnetic cores for transformers to suppress eddy currents.

Magnetic domain

A magnetic domain is a region within a magnetic material in which the magnetization is in a uniform direction. This means that the individual magnetic moments of the atoms are aligned with one another and they point in the same direction. When cooled below a temperature called the Curie temperature, the magnetization of a piece of ferromagnetic material spontaneously divides into many small regions called magnetic domains. The magnetization within each domain points in a uniform direction, but the magnetization of different domains may point in different directions.

Related lectures (57)

Dielectric and Magnetic Properties

Explores dielectric and magnetic properties of materials, including electrical conductivity, insulators, capacitors, and different types of magnetism.

Materials Science of Magnetic Materials

Covers the materials science of magnetic materials, focusing on properties, concepts, and optimization for functional applications.

Soft Magnetic Materials: Fe-Si Alloys to Amorphous Alloys

Explores Fe-Si and Ni-Fe soft magnetic materials, discussing their properties, processing, and applications, as well as the benefits of tailored impurities.

Soft Magnets Applications

Covers strategies to optimize magnets for soft magnetic materials applications, including losses in AC applications and historical progress.

Magnetoelastic Effects: Magnetostriction Coefficient