Amorphous Diamond-Like Carbon (ADLC ) · Kyon Symposium 2010 / MT 13.11.2010 Amorphous Diamond-Like Carbon (ADLC ) Ionbond AG Olten Dr. M. Tobler 13. November 2010

Kyon Symposium 2010 / MT 13.11.2010

Amorphous Diamond-Like Carbon (ADLC )

Ionbond AG Olten Dr. M. Tobler

13. November 2010


Solid : Molecules fix in lattice

Ice (T < 0°C)

Liquid : Limited motion of molecules

Water (0°C < T < 100°C)

Gas : Motion of molecules over large distances

Water vapour (T > 100°C)

Plasma : Molecules, Electrons & Ions, motion over large distances

Ionized Gas (T > 10 000°C, 10eV)

EN

ER

GY

Plasma : 4th state of materials


Natural plasma

Techn. plasma

Plasma phenomena


CVD - PVD

! PVD - Process : Physical Vapour Deposition "  Evaporation of solid metal (arc, magnetron, electron beam etc.) "  Reaction energy provided by plasma excitation ! electrical field "  Line-of-sight Process "  Mixed sources possible, ± any metals usable "  Deposition of metastable phases "  TiN, CrN, ZrN, TiCN, TiAlN, AlTiN, WC/C …….

! CVD - Process : Chemical Vapour Deposition "  volatile starting materials (gases) "  Reaction energy provided by temperature ! Thermodynamics "  No line of sight process "  Limited options for starting materials (evaporation temperature,

reactivity) "  TiN, TiCN, TiC, Al2O3, Cr2C7


PACVD-Process

#  PACVD - Prozesse : Plasma Assisted CVD "  volatile starting materials (! CVD)

"  energy input by plasma excitation(! PVD) Combination

$  Advantages : !  Reduction of reaction temperature (~1000°C ! < 200°C) !  3D- & inside surface accessible for coating

%  Limitations : !  Plasma- & vacuum technology !  Starting materials (composition, price, toxicity....)


Carbon modifications

extremely hard electrical insulator thermal conductor metastable modification transparent

very soft electrical conductor

thermal conductor stable modification

black

Diamond (sp3) Graphite (sp2)


Carbon coatings

VDI 2840 : 2004-1


ta-C:H (3.0 g/cm3) 25% H

sp2 – 14% sp3 – 86%

a-C:H (1.7g/cm3) 30% H sp – 15% sp2 – 65% sp3 – 20%

Hybridisation


PACVD Process

Disadvantages : Volatile precursors Creation of by-products RF-Process : Bias = f(A)

Advantages : no line-of-sight Process Any moving parts High usable volume No targets & power supplies Smooth coatings

CH3+

C2H2

CxHy+

H2+

C2H2+

CxHy+

H2 CH+

CH2+

H+

Ar, H2, CxHy,

Precursor

Bias PS

pulsed DC, RF : Insulators coatable and deposition of insulation coatings possible due to compensation of ion current by dielectric current.


ADLC - Process


ADLC process features


ADLC - Structure

ADLC : typical, shell-like, amorphous fracture surface

Steel


SIMS depth profile


ADLC - Properties 1


ADLC - Properties 2


Friction / Hardness


Hardness - Wear coefficient

DLC Type


Tribotest (oszillating)

Wear rate (ADLC) : ~8"10-8 mm#/Nm Wear rate (Pin) : ~6"10-9 mm#/Nm

Disc: ADLC-R coated Ball : 100Cr6 , Ø6mm

Conditions : Load = 10N Temp. = RT Duration = 10h


Wear rate


Industrial used properties of ADLC

Friction coefficient : 0.04 - 0.1 (dry) ! Bearings (chemical pumps, turbo charger) ! Tools & Components (forming tools)

Wear coefficient : < 10 -16 m!/N ! Machine & automotive industry (high pressure pumps)

Surface smoothness : PACVD-Process ! Precision technology (stamps, high precision tools, dosing pumps)

Chemical inertness : completely inert ! Chemistry & Medicine (chemical pumps, implants, instruments)

Colour : black, light adsorption ! Medicine & Decor (instruments, watches, jewellery)


Property Application field Example

Coefficient of friction

Machine industry Slide & Air bearings Piston / Cylinders F1 Engine parts ; Motorcycle forks

Low process temperature

Machine industry High precision components

Textile industry Light weight components

Chemical inertness

Chemistry Slide bearing, ball valves

Medicine Surgical instruments, implants

Hardness , Wear

Machine industry Machine components, Chucks, Tools

Colour Design, Jewellery Watches

Applications


Industrial applications

Turbo charger bearing

Gear pumps

Chuck elements

Plastic injection moulds


CD - Mirror plate

Requirements :

•  extremely low roughness

•  defect free

•  easy recycling


Samples coated

Wear reduction on Hip joints

Reduced light reflection on Scissors, Pincers, Forceps

Requirements : !  cutting force not to be

increased due to coating

Requirements : !  perfect surface finish !  Long term stability

(chemically & mechanically)


uncoated

Implant uncoated - coated

ADLC coated

Any change in surface finish


Strengths & Weaknesses of ADLC

Weaknesses Strengths

Implants Coating structure influenced by

surface & chemistry Chemical inertness, Biocompatibility,

Haemocompatibility No “coating design” (metals) ;

limited coating variations No metals incorporated (leaching)

Supports in stock Masking possible, selectable coating areas

Pinholes High surface quality

Instruments Supports in stock High surface quality without polishing 100% coating area problematic Low coating temperature

Black colour, easy detection of failures


Property Samples prepared

Wear protection Joints (Hip, Knee, Finger, Chin) Spine implants

Surface roughness Heart valves (Flaps & Casing) Finger joints

Reflectivity Ophthalmological instruments Colour Scissors, Pincers, Forceps Surface chemistry Surgical needles, Stents

Pharmaceutical instruments Bioactivity Cell cultures tests

Tests with IonBond ADLC

Substrates : TiAl4V6 ; CoCrMo ; Stainless steel ; Molybdenum


Thanks for your attention

Documents

Amorphous Diamond-Like Carbon (ADLC ) · Kyon Symposium 2010 / MT 13.11.2010 Amorphous Diamond-Like Carbon (ADLC ) Ionbond AG Olten Dr. M. Tobler 13. November 2010