Abstract
The character and role of grain boundaries in NdFeB alloys and magnets are described and discussed. The role of the grain boundaries in the hydrogen decrepitation process is considered and the influence of the character and mobility of grain boundaries on the properties of fully dense sintered magnets is described. Grain boundaries also play an important role in the hydrogenation disproportionation desorption and recombination process whereby the coarse grain, cast material is converted to very fine grain particles.
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© 2002 Carl Hanser Verlag, München
Artikel in diesem Heft
- Frontmatter
- Editorial
- Editorial
- Articles/Aufsätze
- Interplay between chemical and magnetic roughness of Pt in a Pt/Co bilayer investigated with X-ray resonant magnetic reflectometry
- Thermal stability and magnetic anisotropy dispersion in high-density hard-disk media
- Thickness dependence of magnetization structures in thin Permalloy rectangles
- Solving the selectivity problem in magnetic random access memories using configurations that form C-states
- Second-order magnetoelastic effects: From the Dirac equation to the magnetic properties of ultrathin epitaxial films for magnetic thin-film applications
- Magnetic relaxation in nanocrystalline systems: linking Monte Carlo steps with time
- Effect of domain size on the magneto-elastic damping in amorphous ferromagnetic metals
- The character and role of grain boundaries in NdFeB-type alloys and magnets
- Magnetic domain structure and spin reorientation process
- Magnetic properties of Tb(Fe, Mo)12 and Tb(Fe, Mo)12C compounds
- Microstructure, magnetic properties and magnetic hardening in 2 : 17 Sm–Co magnets
- Micromagnetism and microstructure – tailoring of high-performance permanent magnets
- Metastable alloys at moderate cooling rates
- Thermal critical phenomena and crossover between critical regimes in ferromagnets with long-range interactions
- Vacancies in thermal equilibrium and ferromagnetism near the Curie temperature
- The vortex lattice in superconductors
- Functional substrates – a novel approach to tailor transport properties and flux-line pinning in YBa2Cu3O7 – x thin films
- Superconducting permanent magnets and their application in magnetic levitation
- Magneto-optical studies of flux pinning in high-temperature superconductors
- Atomic transport in amorphous metals
- A novel technique for measuring diffusivities of short-lived radioisotopes in solids
- Hydrogen four-level tunnel systems in substitutional body-centred cubic alloys
- Magnetic relaxation phenomena in cobalt
- The Verwey transition in magnetite as studied by means of definite impurity doping
- Notifications/Mitteilungen
- Personal/Personelles
- Bücher/Books
- Conferences/Konferenzen
- DGM Training/DGM Fortbildung
Artikel in diesem Heft
- Frontmatter
- Editorial
- Editorial
- Articles/Aufsätze
- Interplay between chemical and magnetic roughness of Pt in a Pt/Co bilayer investigated with X-ray resonant magnetic reflectometry
- Thermal stability and magnetic anisotropy dispersion in high-density hard-disk media
- Thickness dependence of magnetization structures in thin Permalloy rectangles
- Solving the selectivity problem in magnetic random access memories using configurations that form C-states
- Second-order magnetoelastic effects: From the Dirac equation to the magnetic properties of ultrathin epitaxial films for magnetic thin-film applications
- Magnetic relaxation in nanocrystalline systems: linking Monte Carlo steps with time
- Effect of domain size on the magneto-elastic damping in amorphous ferromagnetic metals
- The character and role of grain boundaries in NdFeB-type alloys and magnets
- Magnetic domain structure and spin reorientation process
- Magnetic properties of Tb(Fe, Mo)12 and Tb(Fe, Mo)12C compounds
- Microstructure, magnetic properties and magnetic hardening in 2 : 17 Sm–Co magnets
- Micromagnetism and microstructure – tailoring of high-performance permanent magnets
- Metastable alloys at moderate cooling rates
- Thermal critical phenomena and crossover between critical regimes in ferromagnets with long-range interactions
- Vacancies in thermal equilibrium and ferromagnetism near the Curie temperature
- The vortex lattice in superconductors
- Functional substrates – a novel approach to tailor transport properties and flux-line pinning in YBa2Cu3O7 – x thin films
- Superconducting permanent magnets and their application in magnetic levitation
- Magneto-optical studies of flux pinning in high-temperature superconductors
- Atomic transport in amorphous metals
- A novel technique for measuring diffusivities of short-lived radioisotopes in solids
- Hydrogen four-level tunnel systems in substitutional body-centred cubic alloys
- Magnetic relaxation phenomena in cobalt
- The Verwey transition in magnetite as studied by means of definite impurity doping
- Notifications/Mitteilungen
- Personal/Personelles
- Bücher/Books
- Conferences/Konferenzen
- DGM Training/DGM Fortbildung