Politecnico di Torino | |||||||||||||||||
Anno Accademico 2016/17 | |||||||||||||||||
01LDVRU Magnetismo nei materiali e misure magnetiche |
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Dottorato di ricerca in Metrologia - Torino |
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Presentazione
PERIODO: GIUGNO 2017
Il corso sarà tenuto da V.Basso/M.Kuepferling dell' I.N.RI.M. - Sezione Materiali. - Il corso intende fornire le basi per comprendere gli aspetti metrologici del magnetismo, la fisica dei materiali magnetici e le associate tecniche di misurazione. Darà una introduzione a - concetti di base nel magnetismo - origine quantistica del ferromagnetismo - teorie del processo di magnetizzazione - materiali per applicazioni tecnologiche - tecniche sperimentali Il corso si svolgerà nella sala riunioni del primo piano dell’edificio D dell’INRIM in Strada delle Cacce 91, Torino e si tiene in inglese. Il corso è aperto a tutti gli interessati. Chiunque intenda partecipare può inviare una e-mail di conferma a m.kuepferling@inrim.it, v.basso@inrim.it, per rimanere aggiornato su eventuali cambiamenti. The course will provide the basis to understand the metrological aspects of magnetism, the physics of modern magnetic materials and the associated measurement techniques. It will give an introduction to - basic concepts in magnetism - quantum origin of ferromagnetism - theories of magnetization process - materials for technological applications - experimental techniques Place: Meeting room at the first floor of Building D, INRIM, Strada delle Cacce 91, Torino. The lectures are in English. Interested students should send a confirmation email to m.kuepferling@inrim.it, v.basso@inrim.it, to be updated on last minute changes. |
Programma
Lecture 1 : Introduction to magnetism and magnetic materials (2 hours, MK)
1.1 Magnetism and technology: importance of magnetic materials 1.2 Overview of the basic concepts of magnetism. 1.3 Orbital magnetic moment: Bohr magneton; diamagnetism. Lecture 2 : Magnetism and Maxwell equations (2 hours, VB) 2.1 Magnetic media in Maxwell equations 2.2 Magnetostatics Lecture 3 : Microscopic origin of magnetism (2 hours, MK) 3.1 Paramagnetism 3.2 Ferro-, antiferro- and ferrimagnetism 3.2.1 Molecular field theory and Curie temperature 3.2.2 Spin magnetic moment 3.2.3 direct exchange (Heisenberg) 3.2.4 indirect exchange (oxides and metals) 3.2.5 itinerant magnetism Lecture 4 : Energy terms of a ferromagnet (2 hours, VB) 4.1 Zeeman energy 4.2 Magnetostatic energy 4.3 Exchange energy 4.4 Magnetic anisotropy and magnetoelastic effects 4.5 Summary of magnetic energies Lecture 5 : Domains and domain walls (2 hours, MK) 5.1 Domain walls (DW): energy and width 5.2 Domain structures (closure domains, domains in thin films) 5.3 DW pinning and hysteresis 5.4 Single domain particle (Stoner-Wohlfarth model) 5.5 Superparamagnetism 5.6 Observation of domains: magneto-optics Lecture 6 : Magnetization processes (2 hours, VB) 6.1 Introduction: B-H curve and magnetization process 6.2 Macro- and Micro approach 6.2.1 Hysteresis modelling 6.2.2 Micromagnetics 6.3 Magnetization dynamics Lecture 7 : Measurement techniques (2 hours, VB) 7.1 Generation and measurement of magnetic fields 7.1.1 Solenoids, Helmholtz coils, electromagnet, Halbach 7.1.2 Hall, NMR, pickup coils, Squid... Lecture 8 : Soft magnetic materials (2 hours, MK) 8.1 General properties 8.1.1 Hysteresis loss, eddy current loss 8.1.2 Skin depth, high frequency losses 8.2 Materials and applications 8.2.1 static: Fe, Fe-Co 8.2.2 low frequency: Si-Fe, Fe-Ni, Fe-Co and amorphous materials 8.2.3 high frequency: Soft ferrites, YIG 8.3 Magnetization measurements 8.3.1 Hysteresisgraph - wattmeter 8.3.2 Barkhausen noise measurement 8.3.3 Susceptibility: ballistic method Lecture 9 : Hard magnetic materials (2 hours, VB) 9.1 General properties (M-H, B-H, (BH)max) 9.2 Materials 9.2.1 Alnico 9.2.2 Hexagonal ferrites 9.2.3 Rare Earth-Transition Metal Intermetallics 9.2.4 Other 9.3 Magnetization measurements 9.3.1 Hysteresisgraph (hard material) 9.3.2 Vibrating Sample Magnetometer 9.3.3 Pulsed field magnetometer (hard materials) 9.3.4 Anisotropy: torque measurement, SPD. Lecture 10 : Special topic: Spintronics (2 hours, MK) |
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Statistiche superamento esami |
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