Program of the First International Summer School

“Multi-scale texturing of surfaces and multi-physical interactions”

July, 1st and 2nd 2019 – Lyon - Ecole Centrale de Lyon - France

https://www.openstreetmap.org/#map=18/45.78328/4.76767

Wetting phenomena and textured surfaces

Elise Contraires

University of Lyon, Laboratoire de Tribologie et Dynamique des Systèmes. UMR

5513, ECL – ENISE – ENTPE - France

This course deals with surface tension phenomena and one of its consequence

which is wetting.

After a brief definition and recall of surface tension physical and mechanical

origins, the situation of wetting is detailed. One will define the parameters with

an influence on wetting phenomena, the methods used to measure contact

angles and their limitations.

A focus is made on the wetting on textured surfaces, which is a widespread

situation in everyday life and which can be a solution for many technological

applications. The common models are presented, and extended to current

surface with specific topography. Then more recent advances in the field of

wetting on textured surfaces are presented and the models are implemented.

The last part is dedicated to dynamic wetting phenomena, in particular for

textured surfaces. Three situations are detailed: imbibition and spreading, flow

and advancing of contact line and impact of drops on textured surfaces.

The aim of this course is to give a general view of recent advances of wetting,

especially for textured surfaces, with an opening to potential applications for

industry. The actual limits challenges are presented.

Biography

Elise Contraires is an assistant professor from Ecole Centrale de Lyon, in the

Laboratory of Tribology and System Dynamics. She deals with wetting problema

on textured surfaces, particularly in the case of dynamic wetting. She develops

specific experiments for the displacement of droplets on textured or chemically

- modified surfaces, with the help of mechanical vibrations.

She is an expert in physical chemistry of surfaces with an application to wetting

and adhesion.

Colour appearance of materials

Sophie Jost University of Lyon, Laboratoire de Tribologie et Dynamique des Systèmes. UMR

5513, ECL – ENISE – ENTPE - France

Material appearance results from the interpretation by the human visual system

of the interaction between light and matter. Colour appearance brings

together different scientific domains from physical characterization to

physiological sensation. Optics is the study of light and its interaction with

matter. Light, from a light source or issued from a surface, can be characterized

by its energy, its wavelength, its direction but it would not be accurate to say

that it “has a colour”. To produce colour, the radiation needs to enter the

human visual system then the brain will interpret the signal to produce

appearance attributes.

In this course, the three elements of the model will be overlooked. First light and

radiometry will be presented. Then the physical properties of materials will be

studied. Some concept of colour vision will be introduced to understand

colorimetry. Finally, colour appearance models will be presented to show the

correlation between optical phenomena and appearance attributes.

Biography: After engineering studies at ENTPE-Lyon and a MSc in building and sustainable development at INSA-Lyon (graduated in 2006), Sophie Jost completed a PhD on Visual Characterization of Color Quality for LED Light Sources. Since 2012 she is a researcher at the Building and Civil Engineering Laboratory at ENTPE. Her research interests are visual perception and lighting quality and particularly color rendering, colour appearance and phychophysics. She is a member of the International commission of Illumination (CIE) and she is the French representative for the division 1 (color and vision).

Roughness and Non - Newtonian effects on lubricated contacts

Benyebka BOU-SAÏD

University of Lyon, CNRS INSA-Lyon, LaMCoS, UMR5259, F-69621, France

Abstract

Commonly, studies of hydrodynamic lubrication behavior focus on the

performance of mechanisms lubricated with a Newtonian viscous fluid;

however, it is found that the Newtonian fluid constitutive approximation cannot

satisfy engineering demands of modern lubricants. Indeed, the experiments

have shown that the base oil blended with some long-chain additives to a

Newtonian fluid gives the most preferable lubricants and can improve

lubrication properties. The use of additives has beneficial effects on the friction

characteristics and wear of the friction material, which results in longer

mechanism life. To better describe the rheological behavior of these kinds of

non-Newtonian fluids, the Stokes micro-continuum theory which accounts for

polar effects in the form of couple stress, body couples and asymmetric tensors

can be used. It is noteworthy to recall that mainly, studies assume that the

contact surfaces of these lubricated mechanisms are completely smooth.

However, this hypothesis is not realistic because all surfaces are rough. When

the roughness and the film thickness are in the same order of magnitude, the

surface roughness has a noticeable effect and must be considered when

dealing with the hydrodynamic or elasto-hydrodynamic lubrication

performances. One of the methods used to assume theoretically the effect of

roughness is homogenization. Homogenization method based on an

asymptotic expansion is a mathematical theory which includes the study of

partial differential equations with rapid oscillation coefficient. Some of contact

surfaces are deformed because of the existence of high pressure into the

lubricant. It is advisable to consider the deformation of surfaces in lubricated

contacts, such as the typical study of micro-roughness effects in elasto-

hydrodynamic lubrication problems.

In this presentation we will focus on a numerical investigation when coupling

the non-Newtonian couple stress, stationary surface roughness and

deformation effects upon the performance of lubricated contacts by

homogenization method. The homogenization method is applied to account

for the roughness effect. The Stokes micro-continuum couple stress model is

used to consider the non-Newtonian effects. The total deformation is

composed of the deformation of smooth stationary surface, considered by the

elastic thin layer model and by the deformation of roughness corresponding to

a sinusoidal normal displacement on an elastic half space of identical

wavelength. Results are presented for transverse, longitudinal and anisotropic

roughness patterns and for different values of the couple stress parameter.

Biography

Benyebka Bou-Said is Professor at INSA de Lyon and researcher at LaMCoS in a

variety of subjects concerned with both fundamental and applied tribology,

including hydrodynamics, fluid-structure interaction, rheology, tribochemistry

and biomechanics (joint and vascular diseases). Pr. Bou-Said's background in

tribology encompasses bearings, dampers, magnetic devices, including both

fluid film and fluid-structure coupling and bio-tribology. Pr. Bou-Saïd is the head

of a research group involved in Tribology. He is the supervisor of more than 42

PhD thesis and 80 Research Master

Pr Bou-Saïd is Fellow ASME and STLE , guest editor for the Journal of Engineering

Tribology (JET) and Tribology International and associate editor for Tribology

Transactions and JET.

Pr. Bou-Saïd is listed in the Who’s Who in the World and has authored more than

100 papers. He has received the Tribology Gold Medal at the Japanese

Tribology Conference Nagasaki October 2000 for his prospective work in the

field of biotribology.

Considering surfaces roughness in fluid film lubrication models

Noël Brunetière

Institut Pprime – Poitiers University - France

The objectives in reduction of energy consumption and polluting emission require the

use of low viscosity oils leading to thinner lubricant fluid films in machine elements. The

occurrence of mixed lubrication regime, characterized by a partial asperities contact

due to reduced surfaces distance, becomes more recurrent making it necessary to

consider the effect of surface roughness in fluid film lubrication models.

After a short description of the fluid film lubrication theory, it will be shown how surface

roughness can make the traditional lubrication assumption obsolete. Usual models to

include the effect of roughness, that are based on averaging and homogenization,

will be presented and compared to direct numerical solutions. The accuracy and

computation efficiency will be more particularly analyzed. The advantages and

drawbacks of each approaches will be presented and discussed. Then, more recent

multi-scale methods will be introduced. The assets of these approaches will be

demonstrated on a few examples.

Biography

Noël Brunetière is a 45 year old, CNRS Director of Research, with more than 20 years of

experience on lubrication sciences. Since 2008, his research is more particularly

focused on the mixed lubrication regime and the effect of surface roughness on

lubrication. He has authored or co-authored 52 papers in International journals with a

h-index of 20 (google scholar). He is an associate editor of the ASME Journal of

Tribology and of Tribology Online. He was the leader of the Tribology Group in Pprime

(2012-2013) and is at the Head of the Joint Lab Lerded with CETIM since 2012.

Surface Engineering by depositon of thick protective coatings

I. Smurova,b, M. Doubenskaiaa,b, V. Ulianitskyc, A. Travianovb

aLyon University, ENISE, LTDS Laboratory, UMR CNRS 5513, 58 rue Jean Parot, 42023 Saint-Étienne Cedex 2, France

bNation University of Science & Technology (MISIS), 4 Leninsky pr., 119049, Moscow, Russia

cLavrentyev Institute of Hydrodynamics SB RAS, Novosibirsk, Russia

This part of lectures on Surface Engineering is related to deposition of thick (normally

in the range 100 – 300 µm) protective coatings by Thermal Spraying Technologies (TS),

as for example, High Velocity Oxygen Fuelling, Plasma Spraying, Detonation Spraying,

Cold Gas Dynamic Spraying. Laser Cladding is concerned as well. The wear, thermal

and corrosion resistant coatings with low friction coefficient are composed from

metals, alloys, cermet, and ceramics based on powder.

TS coatings can be deposited on substrates made from metals, ceramics, plastics,

even wood and can coat surfaces of arbitrary shapes with an incidence angle up to

60 degrees. For the majority of materials the coating thickness can exceed several

hundreds of microns.

Measurements of the particle-in-flight velocity using optical diagnostics were

performed.

Biography

PERSONAL INFORMATION

Family name, First name: SMUROV Igor

Nationality: French

Date of birth: 12/01/1954

• EDUCATION

1977 Engineer-physicist

Faculty of Theoretical and Applied Physics, Moscow Physical Engineering

Institute, Russia

1982 PhD

Baikov’s Institute of Metallurgy and Material Sciences, USSR Academy of

Sciences, Russia

1993 Qualification of University Professor, delivered by French National University

Committee, Section 60 (Mechanics and Civil Engineering).

• CURRENT POSITION(S)

1993 – present University Professor

National Engineering School of Saint-Etienne (ENISE), France

2001 – 2011 Director of Laboratory

Laboratory “Diagnostic and Engineering of Industrial Processes” (DIPI),

National Engineering School of Saint-Etienne (ENISE), France

2011 – 2016 Director of Laboratory

Laboratory of “Innovative Additive Technologies” (LIAT),

Moscow State Technical University “Stankin” • FELLOWSHIPS AND AWARDS

2011 - 2014 Prof. I. Smurov was awarded for various Advance Technologies of Laser

Assisted Additive Manufacturing: 8 gold, 3 silver and 1 Grand Prix of various

Inventions and Innovation Forums.

• PUBLICATIONS

More than 450 publications including 3 books, 17 invited articles in the books, 221 articles in

International journals, 15 patents. H-index (Scopus, considering scientific production since 1995)

equals 37.

Surface metrology for the automotive industry -metrology for technically- and economically sustainable vehicles

BG. ROSEN & Lars ERIKSON

Halmstad University - Sweeden

This lecture will give an overview of Automotive tribology, and human perception of

surfaces and continue to exemplify metrology and manufacturing of functional

surfaces using recent and on-going projects at Halmstad University and their Rydberg

laboratory.

Automotive cylinder liner surfaces will be in focus to exemplify the tribology, metrology

and manufacturing of drive-train surfaces. The novel research area of human

perception and surfaces will be introduced from the users point of view and

exemplified with the ongoing research on sustainable injection moulding plastic

components for car- and truck interiors as well as polishing methods to enable

sustainable painting.

keywords for the lecture: engine tribology, sustainable surface engineering, 2D- and

3D-characterization, honing, laser texturing, polishing, defect characterization, texture

segmentation, Hough-transform, traceology, multiscale, relocation technique, Kan-

sei, hard- and soft metrology, injection moulded plastic, sustainable painting, paint

polishing

CVs:

Professor Bengt-Göran Rosén, BG, got his PhD in 1994 and has been leading a research

team focusing on Automotive and functional surfaces in close co-operation with the

Swedish automotive industry with highly competitive internationally companies like

Volvo Cars, Volvo Truck, Scania and the former Saab company and its sub

suppliers. BG has been active in the ISO TC-213 standardisation of surface texture

characterisation and metrology since the 1990'ies and is currently vice chairman of

the Swedish Production Academy and has been the organizer of the Met&props

conference three times in Sweden -1997, 2003 and the latest in 2017.

Lars Eriksson is Professor in industrial design at Jönköping University in Sweden

since 2008 and has been working as an Industrial designer since 1994 when he

was

graduated with a Master of Fine Art at the School of Design Umea University in

Sweden. He has been working 11 years as Industrial Designer with over 30

industrial clients, in total included research and educational company

collaboration over 100 clients. Lars is working with education and research with

a focus on Industrial design in general and surface properties in specific. His

research profile is with Industrial Design with a special focus on surface

properties with a functional approach as example ongoing projects with the

automotive industry in perception of automotive interior surfaces and

repplacement of toxic chromium coatings of plastics.

Optical methods for experimental mechanics: an introduction to

image correlation

Jerome Molimard

Centre Ingénierie et Santé

Ingénierie des Surfaces et Tissus Biologiques (STBio) - France

Optical methods are commonly used in experimental mechanics known as

“photomechanics”. We propose here an introduction to a specific class of methods

based on the Intercorrelation of sub-images. The lecture will present:

1. Introduction: Why should we use optical techniques?

2. Image formation and digitalization (CCD sensors, lens distortion, image

storing)

3. 2D correlation for plane objects (how to write the correlation product?, error

propagation, example)

4. Shape measurement and 2D3C correlation (principle of triangulation, shape

measurement, the role of calibration process, example)

5. On step beyond: Digital Volume Correlation, the cutting edge in

experimental mechanics (example)

6. Toward optimized conditions (What is a good speckle pattern?, What can be

done when discontinuities appear?)

Biography

J. MOLIMARD obtained a MSc (1994) and later a PhD (1999) in Mechanical

Engineering from INSA de Lyon – France. He has been recruited at Mines Saint-

Etienne – France in 2000, to develop experimental mechanics research topics.

He published reference works on shearing interferometry, FEMU identification

methods, or optical metrology. He is winner of the Hetteny award for best

paper in experimental mechanics in 2009. Since that date, he joined the Soft

Tissues Biomechanics department where he oriented his research topic on skin,

and deeper soft tissues / textile-based medical devices interaction (knee

braces, lumbar belts, or compression bands). His contributions enhance the

dialogue between numerical, experimental and clinical points of view to get

a fruitful understanding helping MDs or industry supplies to develop better

patient care protocol. J. Molimard participates to “Experimental methods” and

“Biomechanics” course and is in charge of the “Experimental Mechanics”

course for St Etienne Graduate program; he is authored two books in this field.

Form 2000 on, J. MOLIMARD supervised or co-supervised 15 PhD works, and co-

authored more than 100 conferences and 60 papers in peer-reviewed journals.

Road surface texture and tire/road interaction

Minh-Tan Do

IFSTTAR, AME-EASE, 44344 Bouguenais - France

The presentation deals with the role of road surface texture in tire/road friction and

wear. Definitions of the road surface macro- and microtexture scales are given.

Friction forces are generated by molecular liaisons (adhesion component) and

rubber dissipated energy (hysteresis component). The relationship between texture

and friction, mainly the multiscale contribution of the texture, is presented and

discussed. Contaminants such as water from rainfall and particles from atmospheric

dust and traffic debris reduce friction, mainly the adhesion component. Mechanisms

involved in the lubrication of the tire/road interface are described. The role of the

macro- and microtexture to restore direct contact is presented. Traffic and climate

modify the surface texture and affect friction. Microscopic observations show that

attributing the skid resistance evolution to texture polishing might be too simplistic

and other damage mechanisms must be considered.

Biography

Minh-Tan Do is a senior researcher at IFSTTAR (formerly LCPC). Dr. Do graduated at

the French Civil Engineering School ENTPE in Lyon. He completed his Master of

Sciences and PhD at the University of Sherbrooke in Canada in the field of fatigue of

concrete. He joined LCPC in 1992 and has been applying tribology’s concepts to the

study of skid resistance of roads, runways and metro rolling tracks. His main research

interests are surface microtexture, effect of contaminants on friction, wear and skid

resistance evolution, harmonization of friction measurement methods and driver

warning under adverse weather conditions.

Analysis of complex surfaces with Mountains® 8.0"

François Blateyron

Digital Surf - France

Exploration of specific tools of MountainsMap® for the analysis of structured surfaces

and freeform surfaces, with a preview of new tools from the new version 8. Special

focus will be put on the automatic detection and characterization of periodical

features and on the challenges raised by complex surfaces compared to classical

surfaces. With a discussion on the future of surface texture on freeform surfaces used

in additive manufacturing.

Biography

François Blateyron has been working in the field of surface metrology for more than 25

years. He is expert at ISO TC213 for the development of international standards on

surface texture and filtration techniques, and a regular member of conferences and

journal scientific committees. He is co-director and co-owner of Digital Surf in France,

developer of MountainsMap®, the leading surface analysis software used by the

majority of instrument manufacturers around the world. François also contributes to

educational resources on surface metrology such as the Surface Metrology Guide

(www.surfacemetrology.guide)

Methodologies for surface data characterization.

Aareal parameters as outlined in ISO25178

Liam BLUNT

Huddersfield University – UK

The Course will cover the methodologies for surface data characterisation and will

include areal parameters as outlined in ISO25178. The seminar introduce the distinction

between field parameters and feature parameters. In addition the ideal of the scale

limited surface will be outlined. Where appropriate the course will be illustrated with

appropriate case study exemplars across bio medical, automotive and electronics

industries electronics

Biography Professor Liam Blunt has an honours degree in Materials Technology and a PhD in "The

Metallurgy of Centreless Ground surfaces" under the supervision of Dr Wilf Tomlinson at

Coventry University. Prof Blunt also spent one year working as a metallurgist in failure

analysis at AMTAC Laboratories in Manchester.

His Academic experience includes Post Doctoral period at Warwick

University covering Microscopy of Thick and Thin Film Superconductors. Prof Blunt then

moved onto Birmingham University in 1990 to work on the development of a multi

properties materials tester. Whilst at Birmingham he developed an interest in tribology

and surface metrology. Eventually Prof Blunt secured a lectureship and developed his

research in the field of surface metrology.

In 1997 Prof Blunt moved to Huddersfield and began developing the Centre for

Precision Technologies. As well as teaching in the area of Materials and Manufacturing

processes. During this period the CPT has expanded from three researchers to a fifty

strong activity Prof Blunt has formed extensive industrial collaborations in particular with

Taylor Hobson Ltd a world leading metrology company. Prof Blunt held the Taylor

Hobson Chair of Surface Metrology 2002-2012. Prof Blunt has authored over 300 paper

in the field of surface metrology and tribology. He is a member of the European Society

for Precision Engineering and Nanotechnology (EUSPEN) Governing Council.

Scales and Functional Textures in Manufacturing for Mass

Production

Mohamed EL Mansori

Arts et Métiers ParisTech (France)

In mass production, it is difficult to achieve a scalable and robust technology for

manufacturing with controlled designed functionalities that lead to the solution

"product manufacturability" in industrial conditions. It requires taking into account

upstream (design phase), from the functional needs, the overall quality in terms of

product manufacturability by quantifying the impact of processing conditions on its

functional requirements and service life (especially in the case of severely stressed

products in extreme engineering). The objective of this courses paper is to show how

metrology and tribology can be used to control functional surface design based on

the premise that an intimate connection exists between the physical mechanisms

prevailing during manufacturing and the multi-scale induced - modification on the

produced surfaces. The implementation of this multiscale approach within a mass

production environment allows to correlate the functional performance of the

intolerance designed surface and the manufacturing process of its generation.

The various applications of this multiscale approach also demonstrate that the process

signature should respond in a predictable fashion to change its functional

performance.

Biography

Professor Mohamed EL MANSORI, Arts et Métiers ParisTech, France.

Mohamed EL MANSORI is a Professor at the Department of Mechanical, Material

Science and Manufacturing Engineering, Arts et Métiers ParisTech (France) where he

leads the Mechanics, Surfaces and Material Processing Laboratory (MSMP-EA-

7350)/Engineering. He is appointed as TEES Research Professor at TAMU (USA). He is the

Director Program of TEES-TAMU-ENSAM joint research cluster. He served as Deputy

General Director in Charge of Research & Innovation at the Arts et Métiers ParisTech,

France. He also chaired the Mechanical Engineering and Manufacturing Research

Group (LMPF-EA4106) at the Châlons-en-Champagne campus. He was a founder and

head of project of the creation of the MSMP laboratory, which is a multi-campus

laboratory of the same institution including at Aix-en-Provence, Châlons-en-

Champagne and Lille.

Mohamed EL Mansori received B.Sc degree in Physics from the University of Hassan II

(Casablanca, Morocco:1993), and Ph.D in Mechanical Engineering from the Institut

National Polytechnique de Lorraine (Nancy, France:1997) followed by he was

employed as a post-doctoral researcher at the Center for Advanced Friction Studies

of the Southern Illinois University, USA, and then he joined, before ParisTech, the

research group at the ERMES (Nancy, France) for five years to conduct research

on “the tribological behavior of engineering materials, especially under the influence

of electromagnetic environment”.

His current research interests include the interface of thermo-mechanic characteristics

of both metallic and composite materials and physics behind their tribological and

manufacturing performance. The research activities carried out in the last decade

were interdisciplinary by their very nature. They have been engulfed to the issues

concerning the tribological characteristics of engineering systems and multiscale

advanced manufacturing processes. These activities have led to the formation of a

new research team which conceived and developed the concept of multi-scale

process signature in conjunction with a new tribo-energetic approach for the

fundamental understanding of advanced and sustainable manufacturing processes

involving lightweight synthetic and/or natural reinforced composite materials, energy-

efficient manufacturing processes, advanced tribological studies and new process

development for improved product performance and sustainability, etc. The main

interest of this approach was, in its capability, to "bridge the gap" between the

traditional approaches of academia and the industrial requirements. These resulted

with a strong publication record of more than 160 papers in JCR referenced

international journals and more than 200 international and national conference

proceedings. He has taught many short courses on tribology in the multiscale

manufacturing process. Sevral invitations to technical/scientific meetings and

international conferences can assess his strong international exposure.

Archaeotribology: methods of measurement and characterisation

of arhaeological surfaces

Haris Procopiou

University of Paris 1-Panthéon Sorbonne - France

Haris PROCOPIOU, is professor of archaeology at the university Paris 1-Panthéon

Sorbonne and affiliated to the CNRS UMR 7041 ArScAn. A specialist in prehistoric

agricultural techniques and lapidary technologies in the Aegean world and the

Eastern Mediterranean during the Bronze Age, she applies use wear and residues

analysis. She participated in numerous excavations in Greece and the Near East and

she carried out participative ethnographic enquiries (Greece, India, Tunisia) on

preindustrial techniques. She participated in national (5) and international (6) scientific

projects. She co-directed the project Lyon Science Transfert focusing on the transfer

of ancient skills to current craft and the CNRS project -Technologies Innovantes au

Service de la Pluridisciplinarité. She also coordinated two ANR (National Agency of

Research) projects on the history of prehistoric techniques. These latest studies deal

with the role of senses and emotions during the creation process.

She has been a member of the national committee of the CNRS (Section 32) and she

has provided expertise for different national bodies (HCERES, ANR, Île-de-France, EPHE,

EHESS) for international organisations (Canada (SSHRC), Belgium (ARC), Greece

(Greek Ministry for Education), and also for peer-reviewed international journals. She

has participated in several higher-education selection committees.

She is also part of the reading committee of three journals and is responsible for two

collections (Cahiers Archéologiques, Futures Antérieurs) published by the Éditions de

la Sorbonne.

Currently she is responsible for the master diploma Archéologie, sciences pour

l’archéologie, co-director of the archaeology section and council member of the

department of History of Art and Archaeology and of the École doctorale

d’archéologie ED112. She has supervised about one hundred master theses and

twenty doctoral theses.

Multi-Scale Characterization of surface topography

Prof. Christopher A. Brown, PhD, FASME

Surface Metrology Laboratory

Mechanical Engineering Department

Worcester Polytechnic Institute - USA

Brown earned his PhD at the University of Vermont in 1983. He then spent four years in

the Materials Department at the Swiss Federal Institute of Technology conducting

research on metal surfaces and teaching laboratory exercises. For two years he was

a senior research engineer working on surfaces and on product and process

development at Atlas Copco's European research center. Since the fall of 1989 Chris

has been on the faculty at WPI.

Chris has published over a hundred articles on machining, axiomatic design,

sports engineering, and surface metrology applied to engineering, archeology and

physical anthropology. He has patents on a fractal method for characterizing surface

roughness, an apparatus for friction testing, and on sports equipment. He also

developed software for surface texture analysis.

He teaches grad courses on axiomatic design, and on surface metrology, and

undergraduate courses on manufacturing and on the technology of alpine skiing. He

also consults and teaches courses for industry, on axiomatic design and on surface

metrology. He has been a visiting professor on several occasions in France and Italy,

teaching and doing research on surface metrology and axiomatic design.

Chris co-chaired the first two International Conferences on Surface Metrology

(2009 and 2010) and the first two Seminars on Surface Metrology for the Americas (2011

and 2012) all at WPI, where the goal was to bring together people from all disciplines

working on surface metrology.

He is a past chair of ASME B46, Committee for Classification and Designation of

Surfaces; and he is Director of WPI's Surface Metrology Laboratory.

Femtosecond laser patterning of titanium modifies the contact

stiffness and the forces felt by the cells: in vitro study on stem cell

behavior

V. Dumas 1, C. Mauclair3, A. Guignandon2, H. Zahouani1 1University of Lyon, Ecole Nationale d'Ingénieurs de Saint-Etienne, Laboratoire de

Tribologie et Dynamique des Systèmes, UMR 5513 CNRS, St Etienne 6 France

2University of Lyon, Laboratoire de Biologie des Tissus Ostéoarticulaires, INSERM U1059-SAINBIOSE, St-Etienne.- France

3Université de Lyon, Laboratoire Hubert Curien, UMR 5516 CNRS, St Etienne - France

Surface improvement of implants is essential for achieving a fast osseo-integration. Here, the

femtosecond laser was chosen as an innovative technology for texturing multiscale biomimetic

pattern on a titanium alloy surface. By adjusting the laser parameters, three textures were

made on the titanium surface: two of the textured surfaces (A and B) are composed of a

superposition of micro-craters and ripples (600nm) and the third texture (C) comprises only

ripples. The control of the laser parameters makes it possible to control the diameter (30μm)

and the depth (800nm) of the micro-craters as well as the location and orientation of the

ripples.

In vitro study : Mesenchymal stem cells grown on these surfaces

displayed altered morphometric parameters (see a cell with a stellar

shape on Fig.1), and modified their focal adhesions in term of

number and distribution depending on surface type. Dynamic

analyses of early cellular events showed a higher speed of

spreading on all the textured surfaces as opposed to the polished

titanium. Concerning commitment, all the laser-treated surfaces

strongly inhibited adipogenic commitment and up-regulated osteoblastic.

Elastic model of surface contact : To identify the role of texture scales on cell / titanium

interaction, an elastic model of surface contact has been developed to study the contact

between a cellular plane (equivalent to an extracellular matrix of modulus of elasticity of 5

KPa) and textured titanium with different patterns. The elastic model uses the integral

Boussinesq equation with a loading step every 10 nanometer. For each loading step and after

convergence of the calculation, the force felt by the cellular plane (from 10-11 to 10-7 Newtons),

the contact area and the contact stiffness are determined. The plot of the contact force as a

function of the displacement F = f (δ) clearly shows the effect of a change of scale between

the ripple patterned texture and the cratered patterned surfaces (A, B). This scaling, which

occurs at 270 nanometers, influences contact stiffness, cell forces, and bearing area. This

scaling effect of the printed patterns remains consistent with the morphological analysis which

shows a change of scale in the forces felt by the cells as well as the contact stiffness in the first

small wavelengths of the patterns.

The approaches developed in this study show that the laser texturing of the titanium surface

significantly modifies the mechanics of cell contact according to scales of texture patterns.

The femtosecond laser texturing method offers great versatility in obtaining pattern scales of

textures capable of locally modifying the contact stiffness, the forces felt by the cells and the

stimulation of cellular mechano-transduction. This work will help us understand the cells’

interactions with topographies for the development of textured implants with predictable tissue

integrative properties.

biography

Virginie Dumas is a research engineer in National School of Engineers of Saint-

Etienne. She is involved in several multidisciplinary research projects

(engineering and biology) within the Laboratory of Tribology and Systems

Dynamics (LTDS UMR CNRS 5513.) She has a PhD in Cell Biology in the laboratory

SAINBIOSE specialized in osteoarticular tissues, at the University Jean Monnet,

member of University of Lyon. Her main fundamental research interests are in

vitro effects of surface micro-patterning on cell mechanotransduction and

osteogenesis. Recently, she focused on the influence of surface roughness on

cells behavior for implants fabricated with additive manufacturing.

Hassan Zahouani

➢ Key Data

➢ 1991-1997 Assistant Professor, ENISE – France

➢ 1998 -2006 Full Professor, 60th section (2end class), ENISE - France

➢ 2007 Full Professor, 60th section (1st class), ENISE – France

➢ 2012 Full Professor, 60th section (Exceptional class - 1), ENISE –

France

➢ 2017 Full Professor, 60th section (Exceptional class - 2), ENISE –

France

➢ Research areas:

➢ Surface characterization, multi-scale & Mathematical morphology ,

Rayleigh waves for the characterization of fibrous multi-layer and

anisotropic living tissues, bio-tribology of haptic

➢ 297 articles in peer reviewed journals, 4915 citations, 10 patents, 18

book chapters

➢ H index: 38 (Scholar)

➢ Head of the research team (LTDS – UMR 5513): Mechanics of Material

and Processing

➢ Head of the Engineering platform of Living Tissue (LTDS- UMR 5513)

➢ Chairman of 8 International conferences

➢ Expert for the National Agency of Research

➢ Supervising 62 PhD thesis

➢ Honors

• Associate Professor at Halmstad University

• President of the French Society of Engineering and skin imaging

(created since 1999)

• Expert for AERES (3 times Presidents, 2 times examiner)

• Member of EEMCO: European Group on Efficacy Measurement and

Evaluation of Cosmetics and other Products.

• Best Paper Award. 19th International Conference on WEAR OF

MATERIALS. Portland, Oregon, USA. April 14-18, 2013

• Best Poster AWARD: ACADERM, International Symposium on

Bioengineering and the Skin. San Diego. May 4, 2018

• President of the humanitarian association for the rural population of

Morocco “Treatment of the Eye and Skin”

Rough Contact in Tribology: from Static to Sliding Contact Abdeljalil JOURANI

Laboratoire Roberval FRE UTC/CNRS 2012

University of Technology of Compiègne, France

Email: abdeljalil.jourani@utc.fr

Abstract

The contact phenomenon between two rough surfaces is a subject of

considerable interest and intensive research. Study of the contact of rough

surfaces is very important for the understanding of tribological situations such

as friction, wear, adhesion, manufacturing processes, or fluid leakage. Surface

roughness causes contact to occur only at discrete spots called microcontacts

and a high pressure in the contacting asperities.

Several three-dimensional numerical models were developed in the case of

the static contact using different local geometries of the asperities and

different deformation modes to study the contact between rough surfaces.

The comparison between elastic and elastoplastic models reveals that for a

surface with a low roughness, the elastic approach is sufficient to model the

rough contact. However, for surfaces having a great roughness, the

elastoplastic approach is more appropriate to determine the real area of

contact and pressure distribution. The results of this study show also that the

roughness scale modifies the real contact area and pressure distribution. The

surfaces characterized by high frequencies are less resistant in contact and

present the lowest real area of contact and the most important mean pressure.

The real contact area and pressure field are used as input parameters to

determine the sub-surface stresses, temperature distribution, friction and wear

rate during sliding contact.

The simulations reveal that the temperature at the surface depends strongly on

asperities interactions and mode of surface deformation.

The friction coefficient and wear rate increase with the local slopes of the

roughness. Such effect is related to the increase of the cutting force of each

asperity leading to the transition in dominant wear mode from ploughing to

wedging and cutting.

Biography: Abdeljalil JOURANI is an Assistant Professor in materials science and

tribology in University of Technology of Compiègne, France. His fields of interests

include: the rough contact, the impact of material microstructure on

tribological behavior and the tribology at elevated temperature.

The Bootstrap: a tool to select the relevance scales of the

topography.

Maxence Bigerelle

University of Valenciennes at LAMIH UMR CNRS 8201- France

In many engineering industrial applications, the precise characterization of surface

roughness is of paramount importance because of its considerable influence on the

functionality of manufactured products. Because of the increasing interests from

science and industry, a proliferation of roughness parameters, possibly running into

hundreds, has been triggered to describe the different kinds of surface morphology

with regard to specific functions, properties or applications but also to characterize

materials degradation submit to different mechanisms. In spite of such parameter’s

proliferation, termed by Whitehouse as "parameter rash", there is still no complete

comprehensive view on the relevance of these roughness parameters. Moreover, it is

difficult to choose one (pertinent) parameter rather than another one. In our opinion,

the main objective of methodology is to determine quantitatively and objectively the

most relevant roughness parameters. It includes functional property of manufactured

surface morphology. Moreover, multiscale analysis should be employed to evaluate

the most appropriate scale that should be used for process monitoring. For these

reasons, we propose in this course methodologies to characterize the morphological

properties of a surface in relation to its physical properties. An expert system was

established to quantify the relevancy of roughness parameters which characterize the

functionalities of surfaces at all scales including fractal aspect of the surface for

isotropic or anisotropic surface. The developed computational system includes a

recent powerful statistical technique called the bootstrap method that will be applied

to different studies.

Biography

Maxence Bigerelle is Professor at the University of Valenciennes at LAMIH UMR

CNRS 8201. Engineer in Computer Science, PhD in Mechanics and Ability to

Direct Research in Physical Science, He joined R & D at Arcelor, then Arts et

Métiers School (UMR CNRS UMR 8207). He then joined the University of

Compiègne where he headed the Materials Department (52 people, UMR

CNRS 5253) then joined the LAMIH where he currently directs the Mechanical

Department (120 people) and the Morpho-Mechanical Research Axis (27

people). Authors of more than 150 international publications, his research

activities concern the characterization of rough surfaces and the study of their

physical properties in order to increase their functionalities (optical,

mechanical, chemical, tribological, biological, sensory ...) by their structuring.

He currently leads the Carnot Institutes 'Surfaces Structuring Challenge’, which

brings together nearly a hundred laboratories and technology transfer

organizations.