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Avalanche criticality in externally Avalanche criticality in externally driven materials driven materials Antoni Antoni Planes Antoni Antoni Planes Planes Planes (antoniplanes@ub.edu) Departament Departament de de Fsica Fsica de la


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SLIDE 1

Avalanche criticality in externally Avalanche criticality in externally driven materials driven materials

Antoni Antoni Planes Planes

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

Antoni Antoni Planes Planes

Departament Departament de de Física Física de la de la Matèria Matèria Condensada Condensada Universitat Universitat de Barcelona de Barcelona

(antoniplanes@ub.edu)

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SLIDE 2
  • E. Vives, Ll. Mañosa, J. Baró*, D. Soto-Parra** E. Bonnot***,
  • P. Castillo-Villa**

Present address: *University of Calgary, Canada; * Queen’s University, Belfast; **IPICyT, San Luís Potosí, Mexico

Collaborators

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

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SLIDE 3
  • E. Vives, Ll. Mañosa, J. Baró*, D. Soto-Parra** E. Bonnot***,
  • P. Castillo-Villa**

Present address: *University of Calgary, Canada; * Queen’s University, Belfast; **IPICyT, San Luís Potosí, Mexico

Collaborators

  • B. Ludwig , U. Klemradt

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

  • B. Ludwig , U. Klemradt
  • E. K. H. Salje

C.Gallardo, J. Romero, J. M. Martín-Olalla

  • Y. Fan, R. S. Edwards, S. Dixon
  • R. Romero, M. Stipcich
  • R. Niemann, S. Fälher
  • F. J. Pérez-Reche
  • T. Kakeshita, T. Fukuda
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SLIDE 4

Systems of interest

  • Systems that respond to a slowly driven external field

intermittently with discrete events that occur over a broad range

  • f sizes (avalanches).
  • This behaviour typically occur in heterogenous/disordered

systems with athermal dynamics.

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

  • Examples:
  • Dislocation dynamics
  • Plasticity
  • Fracture
  • Magnetization processes
  • Ferroelastic/martensitic transitions

....

  • Seismicity
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SLIDE 5

Systems of interest

  • Systems that respond to a slowly driven external field

intermittently with discrete events that occur over a broad range

  • f sizes (avalanches).
  • This behaviour typically occur in heterogenous/disordered

systems with athermal dynamics.

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

  • Examples:
  • Dislocation dynamics
  • Plasticity
  • Fracture of porous materials under compression
  • Magnetization processes
  • Ferroelastic/martensitic transitions

....

  • Seismicity
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SLIDE 6

AE occurs associated with these externally stimulated processes. The acoustic waves originates from localized processes that occur at length scales ranging from nano to micrometers that give rise to rapid changes of the internal strain field of the system. It is typically detected in the frequency range of MHz.

Acoustic emission

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

It is typically detected in the frequency range of MHz. Its detection provides a potentially interesting technique to characterize avalanches and avalanche dynamics.

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SLIDE 7

Acoustic source

Acoustic Emission: Elastic waves originate from the source and propagate through the sample.

Electric signal

( )

U t

Piezoelectric transducer (PZT)

A(V)

Detection

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

Acoustic source

Time (ms) Signal, U (t)

Treshold

A

∆t = tend – t0

( )dt

t U E

end

t t∫

2

Example of AE signal:

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SLIDE 8

Data analysis

  • The AE carries the whole temporal and spatial information of the

source mechanism.

  • Extracting this information is difficult since the signal U(t) is

severely distorted due to the acoustic coupling of the transducer and its frequency response.

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

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SLIDE 9

Data analysis

  • The AE carries the whole temporal and spatial information on the

source mechanism.

  • Extracting this information is difficult since the signal U(t) is

severely distorted due to the acoustic coupling of the transducer and its frequency response.

  • Partial information:

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

  • Partial information:
  • Pulse counting rate: Acoustic Emission activity
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SLIDE 10

Examples

Martensitic transition in Cu-Zn-Al

Calorimetry AE activity

Compression of porous Vycor

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

Calorimetry AE activity

1 2 3 4

T (ºC) AE activity

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SLIDE 11

Data analysis

  • The AE carries the whole temporal and spatial information on the

source mechanism.

  • Extracting this information is difficult since the signal U(t) is

severely distorted due to the acoustic coupling of the transducer and its frequency response.

  • Partial information:

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

  • Partial information:
  • Pulse counting rate: Acoustic Emission activity
  • Statistical analysis of the amplitude, energy, duration, waiting-

time, ... of the AE signals: provides information related to the collective behaviour of the system

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SLIDE 12

Criticality

  • Amplitude, energy and duration of AE signals span over a broad

range (decades).

  • Often the statistical distribution of these quantities is power-law

which is a typical feature of criticality, i.e., avalanche dynamics shows scale invariance.

  • Statistical distribution

( )

exp p(Y) C Y Y ω λ

= −

( )

, , : Y A E t = ∆

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

( )

exp

Y Y

p(Y) C Y Y ω λ

= −

λY: measures the distance to criticality CY: normalization factor ω : critical exponent (= α, ε,τ corresponding to A, E, ∆t)

Statistical relation: Scaling relation:

( ) ( )

1 1 1 z x α ε τ − = − = −

     ∆ ∼ ∼

x z

t A A E

  • Criticality

  

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SLIDE 13

Martensitic transition

σ T

  • A martensitic transformation (ferroelastic) is a

diffusionless structural transition from a high symmetry to a lower symmetry crystallographic phase.

  • Can be induced by changing temperature and/or

stress (conjugated field).

  • Shows athermal character and proceeds intermittently as a

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

  • Shows athermal character and proceeds intermittently as a

sequence of jerks (avalanches).

  • Produce a complex multiscale domain microstructure.

Courtesy of Prof. Michel Morin

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SLIDE 14
  • The intermittent (jerky) character of the transformation is a

consequence of dynamical constraints imposed by disorder:

Framework

  • Intrinsic disorder: lattice defects, impurities, etc...
  • Self-generated elastic long-range interaction effects.

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

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SLIDE 15
  • The intermittent (jerky) character of the transformation is a

consequence of dynamical constraints imposed by disorder:

Framework

  • The jerks or avalanches are associated with discontinuities of the

strain (O.P.) associated with the jumps from one metastable state to another metastable state.

  • Intrinsic disorder: lattice defects, impurities, etc...
  • Self-generated: long-range interaction effects.

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

another metastable state.

F O.P O.P

F

O.P

Driving Field Driving Field

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SLIDE 16

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

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SLIDE 17

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

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SLIDE 18

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

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SLIDE 19

AE signals

5 10 15 U (mV)

Martensitic transition of a Cu-Zn-Al alloy Sampling rate: 2 MHz Waiting times ÷ 20

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

1 2 3 Times (ms)

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SLIDE 20

Acoustic and optical activity (2d)

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

Niemann et al., PRB, 89, 216118 (2014)

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SLIDE 21

Acoustic and optical activity (2d)

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

Niemann et al., PRB, 89, 216118 (2014)

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SLIDE 22

J/K)

300 600

  • 3000
  • 2000
  • 1000

220 240 260 280 300 320

n = 1 n = 2

0.5 1.0

action

0.0 0.5 1.0 220 240 260 280 300 320

Annealed at 800 ºC, cooled in air down to RT and cycled Cu-Al-Mn, single crystal: Cubic → orthorhombic

Cycling across the transition

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016 220 240 260 280 300 320

  • 200

200

T (K)

  • 600
  • 300

300

dQ/dT (mJ/K

  • 300

n = 2 n = 9 n =24

220 240 260 280 300 320 0.0 0.5 1.0

T (K)

0.0 0.5 1.0 0.0 0.5

Transformed frac Pérez-Reche et al., PRB, 69, 064101 (2004)

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SLIDE 23

240 250 260 270 280 1x10

6

2x10

6

3x10

6

dN/dT (K

  • 1)

T (K)

240 250 260 270 280 1x10

6

2x10

6

3x10

6

dN/dT (K

  • 1)

T (K)

240 250 260 270 280 1x10

6

2x10

6

3x10

6

up to 1.6x10

7 K
  • 1

dN/dT (K

  • 1)

T (K)

….

n = 1 n = 2 n = 9

Cycling: Acoustic emission

n =27

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

Critical distribution

n =27

α = 2.4

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SLIDE 24

Universality

Cu-based SMA (single & polycrystals)

cubic → m

Symmetry

α ε

Monoclinic

3.0 ± 0.2 2.0 ± 0.2

Orthorhombic

2.4 ± 0.1

  • Tetragonal

2.0 ± 0.3 1.6 ± 0.1

2

1 A E z ⇒ − = α

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

monoclinic cubic → orthorhombic

2

1 A E z ⇒ − = ε

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SLIDE 25

Universality

Cu-based SMA (single & polycrystals)

cubic → m

2

1 A E z ⇒ − = α

Symmetry

α ε

Monoclinic

3.0 ± 0.2 2.0 ± 0.2

Orthorhombic

2.4 ± 0.1 1.7 ± 0.2

Tetragonal

2.0 ± 0.3 1.6 ± 0.1

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

monoclinic cubic → orthorhombic

2

1 A E z ⇒ − = ε

Fe68.8 Pd31.2 (s.c.)

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SLIDE 26

aJ s-1) Calorimetric signal (J/K)

Mixture of phases

Cu-Al-Ni: transformation to a mixture of 18R (monoclinic) and 2H (orthorhombic) phases.

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

AE activity (s-1) AE energy rate (aJ Vives et al, PRB, 94, 024102 (2016)

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SLIDE 27

Statistics at different scales

Cu-Zn-Al, polycrystal: Cubic → monoclinic Acoustic Emission vs. Calorimetry

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

Gallardo et al, PRB, 81, 174102 (2010) Baró et al, JPCM, 26, 126401 (2014)

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SLIDE 28

Stress- vs. strain-induced MT

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

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SLIDE 29

Stress- vs. strain-induced MT

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

The crossover between the two types of criticality is determined by the mode of

  • driving. As one moves from “soft” to “hard” driving the universality class of the

critical point changes from classical order-disorder to a quenched Edwards- Wilkinson universality class. The crossover between the two types of criticality is determined by the mode of

  • driving. As one moves from “soft” to “hard” driving the universality class of the

critical point changes from classical order-disorder to a quenched Edwards- Wilkinson universality class.

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SLIDE 30

Stress- and strain-induced experiments

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

Hard-driving: Strain- controlled experiments Soft-driving: Stress- controlled experiments

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SLIDE 31

Stress- and strain-induced experiments

Sample: Cu-Zn-Al, single crystal Transformation: cubic → monoclinic

Tensile direction: close to the [001] crystallographic direction

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

35 mm 3.95 mm Ø = 5.53 mm2

Soft-driving: Stress- controlled experiments Hard-driving: Strain- controlled experiments

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SLIDE 32

Stress- and strain-induced experiments

Sample: Cu-Zn-Al, single crystal Transformation: cubic → monoclinic

90 100 110 120

(MPa)

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

Soft-driving: Stress- controlled experiments Hard-driving: Strain- controlled experiments

2 4 6 8 70 80 90

ε (%)

σ (M

ε (%)

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SLIDE 33

Stress- vs. strain-induced MT

( )

dA A dA A N

α −

Amplitude distribution Cu-Zn-Al, single crystal; cubic (L21) → monoclinic (18M)

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

( )

dE E dE E N

ε −

Vives et al., PRB, 80, 180101(R) (2009)

Energy distribution

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SLIDE 34

Soft-driving: Evolution during the first cycles ⇒ tuning disorder ⇒ classical criticality Hard-driving: No-evolution ⇒ self-organized criticalitry

Evolution with cycling

Cu-Zn-Al, single crystal; cubic (L21) → monoclinic (18M)

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

self-organized criticalitry Driving

ε α

Hard 1.98 ± 0.03 2.67 ± 0.03 Soft 2.24 ± 0.02 2.95 ± 0.02

From: Vives et al, PRB 80, 180101R (2009).

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SLIDE 35

Reducing variant multiplicity: magnetic field

AE activity

Ni52Mn23Ga25, single crystal ; cubic (L21) → monoclinic (10M)

ε

2.0

  • Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

Amplitude distributions

( )

dA A dA A N

α −

1.5

APL, 94, 121901 (2009)

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SLIDE 36

Reducing variant multiplicity: stress

Ni50.4Mn27.9Ga21.7, single crystal ; cubic (L21) → monoclinic (10M)

AE activity

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

PRB, 86, 214101 (2012)

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SLIDE 37

Reducing variant multiplicity: stress

Ni50.4Mn27.9Ga21.7, single crystal ; cubic (L21) → monoclinic (10M)

AE activity

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

PRB, 86, 214101 (2012)

ε

1.5 2.0 2.5 3.0

α

T MPa H

M

/ 4 . 3 ≅ = β β σ

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SLIDE 38

Waiting times distribution

E

δ

Waiting times between events above given energy thresholds are considered Waiting times (δ ) distribution above a minimum of energy (threshold) in different regions is governed only by the mean event activity 〈r〉 in such a way that the waiting times probability distribution fulfills the following

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

way that the waiting times probability distribution fulfills the following scaling law [P. Bak, et al., PRL 88, 178501 (2002)] :

( )

( )

δ δ r r D Φ =

The scaling function Φ is expected to show double power-law behaviour:

   ∝ Φ

+ − − − ) 2 ( ) 1 (

) (

ξ ν

x x x

for small arguments (1-ν ∼ 1) (related to correlations ) for large arguments (2+ξ >2) (related to the distribution

  • f background activity rates)
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SLIDE 39

Waiting times distribution: scaling

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

From: Baró et al, JPCM, 26, 126401 (2014)].

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SLIDE 40

Non-granular: skeleton containing a network

  • f interconnected nanometer-sized pores with

narrow size distribution.

Porous materials under stress

Failure of porous materials under compression stress is usually preceded by significant precursor activity. Materials:

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

Examples: Vycor, bones, …., porous Ti-Ni Granular: grains touching (and penetrating) each

  • ther. The voids between the grains constitute a

random network of interconnected corridors and pockets (wider pore size distribution ). Examples: Gelsil, alumina, berlinite, minerals (goethite, sandstones, …), …

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SLIDE 41

Porosity: 40% Skeleton (> 98% SiO2) Mean pore diameter 7.5 nm Narrow pore size distribution

100 nm

Vycor

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

Typical sample size 5x3x3mm

Bentz et al (1998)

Experiments Compression rates R: 0.2 kPa/s 1.6 kPa/s 6.5 kPa/s 12.2 kPa/s

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SLIDE 42

Experimental setup

Compression plates with embedded AE piezoelectric transducers

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

Load control

Rt ∝

Refs.: Salje et al., Phil. Mag. Lett. 91, 554–560, (2011) Salje et al., Am. Min. 98, 609 (2013) Laser extensometer

(Fiedler Optoelektronik)

sample plates

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SLIDE 43

Example of experiment

Experiment performed in Vycor (40% porosity) at a rate R = 1.6 kPa/s

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

Good correlation between sample height change and AE activity.

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SLIDE 44

Example of experiment

Experiment performed in Vycor (40% porosity) at a rate R = 1.6 kPa/s

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

Good correlation between sample height change and AE activity.

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SLIDE 45

AE and earthquakes

Both phenomena occur in very different ranges: ×10-30 × 10-10 × 10-7 Earthquakes AE events: labquakes

Available catalogues (California, Japan,..) AE events in compressed Vycor

E: 1010-1018 J x:102- 107 m t: 10-2- 106 h E: 10-18-10-11 J x: ? -10-3 m t: 10-10 - 100 h Statistical analysis:

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

  • Gutenberg-Richter law: energy distribution
  • Omori law: temporal distribution of aftershocks
  • Productivity law: energy dependence of the

distribution of aftershocks

  • Unified scaling law for the distribution of waiting

times Statistical analysis: These laws are power-laws, indicating the absence of characteristic scales and introducing a set of exponents (ε, p, α, 1-ν and 2+ξ).

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SLIDE 46

Energy distribution: Gutenberg-Richter law

Distribution of energies for different time subperiods: Exponent as function of the minimum cut-off.

The log of the number of earthquakes with seismic moment larger than M linearly increases with M :

) 1 . 1 ( log10 ± ≈ − =

>

b bM a N M

Seismic moment-energy relationship:

⇒ + = 8 . 4 2 3 log10 M E

15 . 67 . 1 3 2 1 , ) ( ± ≈ + = ∝

b dE E dE E p ε

ε

R=1.6 kPa/s

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

The exponent is fitted using the maximum likelihood method (see: Clauset et al., Siam, 51 (2009)].

ε = 1.39

From: Baró et al., PRL, 110, 088702 (2013)

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SLIDE 47

Results: Unified scaling law

1-ν = 0.93 2+ξ = 2.45

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

From: Baró et al., PRL, 110, 088702 (2013)

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SLIDE 48

Comparison with eartquakes

Same results including data for earthquakes in California (for different spatial windows) in the period 1981-2011. 1-ν = 0.93 2+ξ = 2.45

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

The overlap show that waiting times display same statistics in spite of the disparity of scales.

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SLIDE 49

Summary : earthquakes vs. labquakes

EARTHQUAKES LABQUAKES Gutenber-Richter

ε

1.67±0.15 1.40±0.05 Omori

p

0.9-1.8 0.75 Productivity

α

0.7-0.9 0.5±0.1 Universal scaling function

1-ν

0.9 0.93

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

function

2+ξ

2.2 2.45

Excellent fulfillement of fundamental statistical laws of earthquakes by AE events during compression of porous Vycor with very similar exponents.

Ref: J. Baró, E. Vives and A. Planes, in Avalanches in Functional Materials and Geophysics,

  • ed. By E. K. H. Salje, A. Saxena and A. Planes, Chap. 3, From Labquakes in Porous Materials

to Earthquakes, Springer-Verlag, 2017 .

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SLIDE 50

Compression of porous Ti-Ni

SEM image:Ti53.7Ni46.4 porosity: 38.9%

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

Soto-Parra et al., PRE, 91, 060401(R) (2015)

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SLIDE 51

Conclusions

  • Acoustic emission provides information on the dynamical

collective behaviour during the martensitic transformations.

  • Avalanche criticality occurs in thermally and stress induced

martensitic transformations after enough cycling across the transition.

  • In MT, critical exponents depend essentially on symmetry change

(variant multiplicity) at the transition and on the driving mechanism.

  • In compressed porous materials acoustic emission can be

Hysteresis, Avalanches and Interfaces in Solid Phase Transformations, Oxford, UK, 19-21 September 2016

  • In compressed porous materials acoustic emission can be

analysed with the same statistical laws governing earthquakes.

  • Critical exponents are very similar to those reported for earthquakes.
  • The study of labquakes in compressed Vycor provides a laboratory

experiment that can be used as a low-scale model for earthquakes with the final aim of predicting earthquake occurrence.

  • In porous Ti-Ni under compression two families of signals can be

identified, that show different criticalities.