1 Mechanical Spectroscopy of Metallic Materials Igor S. Golovin Department of Physical Materials...

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Mechanical Spectroscopy Mechanical Spectroscopy of Metallic Materialsof Metallic Materials

Igor S. GolovinIgor S. Golovin

Department of Physical Materials ScienceDepartment of Physical Materials ScienceNational University of Science and TechnologyNational University of Science and Technology

““Moscow Institute of Steel and Alloys”Moscow Institute of Steel and Alloys”

20102010

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for “Materials Science” and “Physics of Metals” for “Materials Science” and “Physics of Metals” master studentsmaster students

Content:Content:

IntroductionIntroduction BasicsBasics

ApplicationsApplications

17 lectures, 3 practical works, 2 tests17 lectures, 3 practical works, 2 tests

Mechanical Spectroscopy of Metallic MaterialsMechanical Spectroscopy of Metallic Materials

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Introduction

Elasticity: Hooke law in complex form. Theory of elasticity as a background for modern engineering.

Anelasticity vs. Elasticity or Physicists vs. Engineers : Overview from Hooke to our days.

Vibrations and sound from earthquake to violin concert, or how to find a submarine?

Terms and definitions. Rheological approach.


Content:

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Basics 1

Loading: static and dynamic case. Dissipated energy. Internal friction.

Standard anelastic solid. Zener model for “standard solids”.

Thermally activated relaxation processes. Debye equations. Selection rule.

Frequency and temperature dependent damping spectra. Similarities and differences.


Content:

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Basics 2

Point defects relaxations. Selected examples:

The Snoek effect – relaxation due to interstitial atoms “diffusion under stress” in bcc solution;

The Zener effect – relaxation due to reorientation of pairs of substitutional solute atoms.

Gorsky and Finkelstein-Rosin’s effects


Content:

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Basics 3:

Amplitude dependent damping “Dragging” and “break away” models. Contribution from magnetic subsystem.

Relaxation effects caused by interaction of dislocations and point defects: Bordoni, Hasiguti, and Köster effects.

Structural relaxation and relaxation due to phase transitions. Microplasticity. Reversible martensitic transformation.


MT

Content:

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Introduction to experimental techniques:

Torsion pendula

Vibrating reeds

Dynamical mechanical analysers

direct inverted compound

Opportunities,advantages anddisadvantages


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Applications:

Materials:- Crystalline materials: metals, alloys, intermetallic compounds- Amorphous metallic materials & quasicrystals- Cellular materials (foams, sponges, sintered materials)- High damping materials

Phenomena:

- Diffusion (low temperature)- Solubility - Interatomic interaction- Fatigue, microplasticity - Ageing, cold work . . .


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Additionally, a brief overview of scientific contribution to the field made by

Robert Hook

Peter Debye Svante Arrhenius

Clarence ZenerJacobus Snoek Tin Suj Kê

N.N. Davidenkov V.S. Gorsky

will be given


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Internal Friction and Mechanical SpectroscopyInternal Friction and Mechanical Spectroscopy

Lectures are based on the recently published book

Several new pc tests and programs are prepared for students

2007

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High damping alloysHigh damping alloys

Internal Friction and Mechanical SpectroscopyInternal Friction and Mechanical Spectroscopy

Selected example

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Wanted & unwanted vibrations

from earthquakes to high precision cutting tools,from public transport to military needs …

from “yellow submarine” to church bells,from noisy plants to musical concerts …

Wanted & unwanted noise

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Active and passive damping

High- and low damping materials

Different Material itself constructions

Mechanical Spectroscopy Mechanical Spectroscopy of Metallic Materialsof Metallic Materials

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High damping materials (Hidamets):

- Civil engineering: skyscrapers, towers, windmills, bridges

- Transport: tube, trains, cars, aircrafts …

- Machine-building industry: turbines, …

- Military needs: breech-sight, submarines

and much, much more


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High damping materials (HDM):

- How to measure damping ?

- How to compare damping capacity of different materials ?

- How to create materials with high damping capacity ?

- How to estimate efficiency and applicability of chosen materials ?


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1 10 100 10000,1

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10

100

Mg-SiCu-Al-NiMg-Ni

Fe-Mn-XTiNi

Cu-Mn

Fe-Al, Fe-CrMg-Zr

КЧ, ВЧAZ81

SAPferriticsteels

12Cr

C steels18-8

Mg

cast iron

NiFe

AZ31

Al-alloyTi-alloy

BrassBronze

%

B, kg/mm2

PbHDM

Sugimoto diagram:

α = Ψ01σ0.2 × σB

Sp

ecifi

c d

am

pin

g c

ap

acity

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Low damping materials for:

- Musical instruments(tuning forks, drums, timpani, violins …)

- Bells

-Navigation systems, gyroscopes

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Physical mechanismsof high damping and new materials will be discussed


You are welcome at

““Mechanical Spectroscopy Mechanical Spectroscopy

of Metallic Materials”of Metallic Materials”by by

I.S. GolovinI.S. Golovin

([email protected])([email protected])

1 Mechanical Spectroscopy of Metallic Materials Igor S. Golovin Department of Physical Materials...

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