Overview
Français
ABSTRACT
This article studies the major classes of materials for permanent magnets and their properties. These families are the alnicos (isotropic, anisotropic, with directed crystallization and sintered alloys), ferrites (including hard ferrites and soft ferrites), the samarium-cobalt and the neodymium iron boron. Although these materials are the most common, they are nonetheless fragile, hard and brittle. The following materials for permanent magnets have, on their part, more limited applications although they present the advantage of being easily machined, laminated or wiredrawn. This article presents the ductile alloys, manganese-aluminum-carbon alloys, hard martensitic steels and micropowder magnets.
Read this article from a comprehensive knowledge base, updated and supplemented with articles reviewed by scientific committees.
Read the articleAUTHORS
-
Jean-Marie LE BRETON: Doctor of Physics - Professor at the University of Rouen - Materials Physics Group, UMR CNRS 6634, University of Rouen, Faculty of Science and Technology
-
Luc LECHEVALLIER: Doctor of Physics - Lecturer at the IUP Electrical Engineering of the University of Cergy-Pontoise - Materials Physics Group, UMR CNRS 6634, University of Rouen, Faculty of Science and Technology
-
Philippe TENAUD: Engineer - Doctor of Physics - Manager 3MaS (Magnets, Magnetism, Material & Services), La Combe de Lancey
-
Antoine MOREL: Engineer - Doctor of Physics - Methods/Processes Manager, STEELMAG, Saint-Pierre d'Allevard - Update of the 1996 article [D 2 100] by François LEPRINCE-RINGUET.
INTRODUCTION
Permanent magnets are "hard" magnetic materials, i.e. materials which, once magnetized, retain their magnetization at operating temperature. Their magnetic properties are determined primarily by the intrinsic properties of their constituent compounds. They are also highly dependent on the microstructure of the resulting material, linked to the manufacturing process.
Four families of permanent magnet materials account for the bulk of applications on the market. These are alnicos, hard ferrites, samarium-cobalt and neodymium-iron-boron. Other materials exist, but their applications are very limited. These include ductile alloys, manganese-aluminium-carbon alloys, martensitic hard steels and micro-powder magnets.
In this dossier, the different types of permanent magnet materials and their properties are reviewed. The focus is on the characteristics of each type of material, its advantages and disadvantages relative to other materials. The applications of the different types of magnet, and new developments, are presented in the dossier
The Ultimate Scientific and Technical Reference
This article is included in
Conversion of electrical energy
This offer includes:
Knowledge Base
Updated and enriched with articles validated by our scientific committees
Services
A set of exclusive tools to complement the resources
Practical Path
Operational and didactic, to guarantee the acquisition of transversal skills
Doc & Quiz
Interactive articles with quizzes, for constructive reading
Permanent magnets
General features and properties
Statistical and economic data
Please refer to
Also in our database
Bibliography
Standardization
- Magnetic materials – Method for measuring the coercive field of magnetic materials in an open magnetic circuit (classification index: C28-921) - NF EN 10330 - 08-03
- Magnetic materials – Materials for permanent magnets (magnetically hard) – Methods for measuring magnetic properties (Classification index: C28-919) - NF EN 10332 - 03-04
- Quantities and units – General principles. - NF X02-001 - 12-93
- Basic...
Directory
Laboratories (non-exhaustive list)
Groupe de Physique des Matériaux GPM – University of Rouen http://www.univ-rouen.fr/gpm/
Néel Institute – CNRS Grenoble http://neel.cnrs.fr/
Grenoble Electrical Engineering Laboratory
The Ultimate Scientific and Technical Reference
