Electrochemical characterisation speeds up ... prediction of corrosion behaviour E.W. Schuring J.W

download Electrochemical characterisation speeds up ... prediction of corrosion behaviour E.W. Schuring J.W

of 28

  • date post

    23-Apr-2020
  • Category

    Documents

  • view

    1
  • download

    0

Embed Size (px)

Transcript of Electrochemical characterisation speeds up ... prediction of corrosion behaviour E.W. Schuring J.W

  • Electrochemical

    characterisation speeds up prediction of corrosion behaviour

    E.W. Schuring

    J.W. Hooijmans

    April 2013

    ECN-L--13-034

  • www.ecn.nl

    Electrochemical characterisation

    speeds up prediction of corrosion

    behaviour

    E.W. Schuring

    J.W. Hooijmans

    Environment and Energy Engineering;

    Stand 48

  • 2

    • Introduction • Corrosion in real life • Why Electrochemical characterisation of corrosion • Applications

    • corrosion resistance coatings • corrosion behaviour (brazed) joints

    • Available electrochemical corrosion techniques • Standards • Conclusions

    Content

  • 3

    Knowledge development:

    Degradation processes

    Monitoring

    Materials

    Corrosion in real life

    Current status

    • Unplanned failures due to

    corrosion damage

    GDP NL

    610 billion euros

    Direct annual costs

    due to corrosion:

    18.3 Billion Euros

    (3%)

    Early detection of

    corrosion phenomena

    Materials selection Safety

    + Environment

    Knowledge processes

    *20-30% reduction could be achieved using existing knowledge.

    New technologies enable further reduction.

    Barrier quality

  • 4

    Corrosion in real life

  • 5

    Corrosion mechanisms

    Transport of H2O, O2 , NaCl corrosion products etc.

    Sufficient corrosion resistant?

    C: Barrier properties?

    Metal

    D: Uniform corrosion

    followed by pitting

    Me 2+ H2,OH -

    Anodic and

    cathodic reactions

    Uniform corrosion

    A: Inter- / trans-

    granular corrosion

    B: Pitting

  • • Failure prediction for end-users (more sensitive than

    other methods)

    • On-site electrochemical characterisation measurements

    in tanks and on pipeline coatings

    • Determine time dependent quality and barrier properties

    of coatings

    • Reduce testing time

    • Get insight in acting corrosion mechanisms

    Too late !!!

    Unexpected failure fuel tank

    6

    Why electrochemicl characterisation? • Standard test methods like salt spray testing are

    expensive and need long exposition times • Standard characterisation can lead to

    unrightfull acceptance

  • 7

    Electrochemical Corrosion testing • Barrier properties

    • Corrosion rate

    • Time-to-failure prediction

    • Sensors

    • Development accelerated corrosion test methods

    Data fitting  Physical model

    Re Qcoating

    Rcoating Qdl

    Rct

    Element Freedom Value Error Error %

    Re Free(+) 120 N/A N/A

    Qcoating-Q Free(+) 1E-07 N/A N/A

    Qcoating-n Free(+) 0.89 N/A N/A

    Rcoating Free(+) 4800 N/A N/A

    Qdl-Q Free(+) 1E-07 N/A N/A

    Qdl-n Free(+) 0.4 N/A N/A

    Rct Free(+) 0 N/A N/A

    Data File:

    Circuit Model File: R:\Gouwen\corrosie publiciteit\Model coa

    ting.mdl

    Mode: Run Simulation / Freq. Range (0.01 - 100000)

    Maximum Iterations: 100

    Optimization Iterations: 0

    Type of Fitting: Complex

    Type of Weighting: Data-Modulus

    Re Qcoating

    Rcoating

    Element Freedom Value Error Error %

    Re Free(+) 120 N/A N/A

    Qcoating-Q Free(+) 1E-07 N/A N/A

    Qcoating-n Free(+) 0.89 N/A N/A

    Rcoating Free(+) 4800 N/A N/A

    Data File:

    Circuit Model File: R:\Gouwen\corrosie publiciteit\Model coa

    ting.mdl

    Mode: Run Simulation / Freq. Range (0.01 - 100000)

    Maximum Iterations: 100

    Optimization Iterations: 0

    Type of Fitting: Complex

    Type of Weighting: Data-Modulus

    Re Qcoating

    Element Freedom Value Error Error %

    Re Free(+) 120 N/A N/A

    Qcoating-Q Free(+) 1E-07 N/A N/A

    Qcoating-n Free(+) 0.89 N/A N/A

    Data File:

    Circuit Model File: R:\Gouwen\corrosie publiciteit\Model coa

    ting.mdl

    Mode: Run Simulation / Freq. Range (0.01 - 100000)

    Maximum Iterations: 100

    Optimization Iterations: 0

    Type of Fitting: Complex

    Type of Weighting: Data-Modulus

    Z'

    -Z ''

    PC

    0 200 400 600

    kohm

    0

    100

    200

    300

    400

    500

    600

    kohm

    O2, H2O, Na +, Cl-, etc.

    Metaal

    Coating of deklaag

    O2, H2O Na +,Cl- ,etc.

    Na+,OH-Na+,OH- e-e- Fe2+

    geleidende

    paden

    corrosie producten

    Fe2+ e-

    Na+,OH-

    corrosie producten

    1

    2

    3

    4

    Intacte coating

    Te laat!!!

    Bron: M. Mobin, Malik, A.U., Materials Performance, in February 2005, 2, pp. 28-31. Lekkage olie opslag tank

    degradatie

    T oenem

    ende coating degradatie

    1

    Z'

    -Z ''

    Coating+epox

    0 10 20 30 40

    kohm

    0

    10

    20

    30

    40

    kohm

    2

    3

    Methods for corrosion testing

    Z'

    -Z ''

    PC

    0 200 400 600

    kohm

    0

    100

    200

    300

    400

    500

    600

    kohm

    O2, H2O, Na +, Cl-, etc.

    Metaal

    Coating of deklaag

    O2, H2O Na +,Cl- ,etc.

    Na+,OH-Na+,OH- e-e- Fe2+

    geleidende

    paden

    corrosie producten

    Fe2+ e-

    Na+,OH-

    corrosie producten

    1

    2

    3

    4

    Intacte coating

    Te laat!!!

    Bron: M. Mobin, Malik, A.U., Materials Performance, in February 2005, 2, pp. 28-31. Lekkage olie opslag tank

    degradatie

    T oenem

    ende coating degradatie

    1

    Z'

    -Z ''

    Coating+epox

    0 10 20 30 40

    kohm

    0

    10

    20

    30

    40

    kohm

    2

    3

    Z'

    -Z ''

    PC

    0 200 400 600

    kohm

    0

    100

    200

    300

    400

    500

    600

    kohm

    O2, H2O, Na +, Cl-, etc.

    Metaal

    Coating of deklaag

    O2, H2O Na +,Cl- ,etc.

    Na+,OH-Na+,OH- e-e- Fe2+

    geleidende

    paden

    corrosie producten

    Fe2+ e-

    Na+,OH-

    corrosie producten

    1

    2

    3

    4

    Intacte coating

    Te laat!!!

    Bron: M. Mobin, Malik, A.U., Materials Performance, in February 2005, 2, pp. 28-31. Lekkage olie opslag tank

    degradatie

    T oenem

    ende coating degradatie

    1

    Z'

    -Z ''

    Coating+epox

    0 10 20 30 40

    kohm

    0

    10

    20

    30

    40

    kohm

    2

    3

  • 8

    Stepwise Dissolution Method (SDM) vs Salt spray-BLC

    0 10 20 30 40 50 60 70 80 90

    100

    0,0 0,3 0,6 0,9 1,2 1,5

    B LC

    a ft

    e r

    4 5

    d ay

    s [%

    ]

    Accumulated charge after 6 hours SDM [C]

    7075-T6 clad CrO3 anodized - primed material

    Application (SDM):

    Accelerated Corrosion resistance test coatings

  • 9

    Comparison between BLC and SDM – Both show wedging of anodic coating

    BLC (45 days) SDM (6 hours)

    Embedding mass

    Anodic coating

    Aluminum substrate

    Application (SDM):

    Accelerated Corrosion resistance test coatings

    Ex p

    o su

    re s

    id e

  • Re Qcoating

    Rcoating Qdl

    Rct

    Element Freedom Value Error Error %

    Re Free(+) 120 N/A N/A

    Qcoating-Q Free(+) 1E-07 N/A N/A

    Qcoating-n Free(+) 0.89 N/A N/A

    Rcoating Free(+) 4800 N/A N/A

    Qdl-Q Free(+) 1E-07 N/A N/A

    Qdl-n Free(+) 0.4 N/A N/A

    Rct Free(+) 0 N/A N/A

    Data File:

    Circuit Model File: R:\Gouwen\corrosie publiciteit\Model coa

    ting.mdl

    Mode: Run Simulation / Freq. Range (0.01 - 100000)

    Maximum Iterations: 100

    Optimization Iterations: 0

    Type of Fitting: Complex

    Type of Weighting: Data-Modulus

    Re Qcoating

    Rcoating

    Element Freedom Value Error Error %

    Re Free(+) 120 N/A N/A

    Qcoating-Q Free(+) 1E-07 N/A N/A

    Qcoating-n Free(+) 0.89 N/A N/A

    Rcoating Free(+) 4800 N/A N/A

    Data File:

    Circuit Model File: R:\Gouwen\corrosie publiciteit\Model coa

    ting.mdl

    Mode: Run Simulation / Freq. Range (0.01 - 100000)

    Maximum Iterations: 100

    Optimization Iterations: 0

    Type of Fitting: Complex

    Type of Weighting: Data-Modulus

    Re Qcoating

    Element Freedom Value Error Error %

    Re Free(+) 120 N/A N/A

    Qcoating-Q Free(+) 1E-07 N/A N/A

    Qcoating-n Free(+) 0.89 N/A N/A

    Data File:

    Circuit Model File: R:\Gouwen\corrosie publiciteit\Model coa

    ting.mdl

    Mode: Run Simulation / Freq. Range (0.01 - 100000)

    Maximum Iterations: 100

    Optimization Iterations: 0

    Type of Fitting: Complex

    Type of Weighting: Data-Modulus

    Degradation of coating

    system over time

    Physical interpretation Equivalent circuits

    0