FE simulation of interfacial delamination between SiO2 thin film and polymeric substrate

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OATAO is an open access repository that collects the work of Toulouse

researchers and makes it freely available over the web where possible

This is an author’s version published in: http://oatao.univ-toulouse.fr/23315

To cite this version:

Ho, Caroline and Tongne, Amèvi

and Dalverny, Olivier

and

Alexis, Joël

and Lacroix, Loïc

and Dehoux, Anita and Châtel,

Sébastien and Faure, Bruce FE simulation of interfacial

delamination between SiO2 thin film and polymeric substrate.

(2017) In: European Congress and Exhibition on Advanced

Materials, EuroMat 2017, 17 September 2017 - 22 September 2017

(Thessaloniki, Greece).

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1 FE Simulation of Interfacial Delamination

between SiO

₂

Thin Film and Polymeric Substrate

1 _{University of Toulouse; INP / ENIT; LGP Tarbes, France}

2 _{Essilor International R&D}

_{, France}

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2 1. Context

2. Experimental study

3. Numerical modeling of the test

4. Numerical simulation results

5. Conclusions and perspectives

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3 1. Context

2. Experimental study

3. Numerical modeling of the test

4. Numerical simulation results

5. Conclusions and perspectives

General outline

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4 Ophtalmic lens is a complex system (structure and materials)

70% of French population uses vision correction products

~

10% contact lenses

~

60% eyeglasses

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5 Challenge

Delamination after Process Modification

Important

margin of safety

prior to product launch

Need of a better understanding of mechanisms of adhesion

Insufficient adhesion

between

layers can lead to delamination

Simplification of the system

:

Study of Adhesion of SiO

₂

thin film on Hardcoat

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6 1. Context

2. Experimental study

3. Numerical modeling of the test

4. Numerical simulation results

5. Conclusions and perspectives

General outline

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7 Buckling by

compression test

Adhesion Characterization by compression test

F

Experimental Set-up

>

_BO

F

Hutchinson & Suo

analytical model

),

Energy

Release Rate

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8 Video of buckling

SiO

₂

(200 nm)

on lens

Lens

Hardcoat

PC substrate

Aluminum

layer

SiO

2 Configurations of samples

F

Experimental results

Experimental study

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9

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10 Geometry | Boundary conditions

Description of Numerical model

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11 Solving the momentum equation : Instability caused by buckling

Interface degradation using damage model

Physical model

Description of Numerical model

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12 Solving the momentum equation : Instability caused by buckling

Description of Numerical model

Physical model

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13 Solving the momentum equation: Instability caused by buckling

Interface degradation using damage model

Traction Separation Law

Cohesive surface

Cohesive element

Description of Numerical model

Physical model

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14 Cohesive Behavior

Tangential Behavior

Damage Initiation

Damage Evolution

Damage Stabilization

Interfacial Properties

Total Displacement

Viscous Stabilization

Frictionless

Materials Properties

SiO

₂

thin film

E,

Hardcoat

E,

Description of Numerical model

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15 Geometry | Boundary conditions | Mesh

Homogeneous meshing near the

interface

Element Type CPS4, CPS3

Element Size

Defect : x = 10 nm ; y = 0,1 nm

SiO

₂

layer : x = 100 nm ; y = 40 nm

First 100 nm of Hardcoat

x = 100 nm ; y = 20 nm

Numerical modeling of the test

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16 1. Context

2. Experimental study

3. Numerical modeling of the test

4. Numerical simulation results

5. Conclusions and perspectives

General outline

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17 Video of simulated buckling

Numerical simulation results

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18 Initiation Strain

Experimental : 3,8 % strain

Numerical : 3,9 % strain

Numerical simulation results

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19 Buckle Height

Experimental :

Numerical

Buckle Width

Experimental

Numerical

Buckle Height

Buckle Width

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20 1. Context

2. Experimental study

3. Numerical modelling of the test

4. Numerical simulation results

5. Conclusions and perspectives

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21 Model using static calculation with cohesive surface

Buckling obtained with numerical model

Parametric study

Perspectives

Analysis of energy dissipated

Conclusions

Good match of Initiation strain with experimental results

Buckle dimensions to be improved upon

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22 Essilor International

Innovation and Technology Center

ANRT

Research and Technology National Association

Acknowlegments