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Powder Piloting Service

Material solutions, from powder to product.

VTT Technical Research Centre of Finland Ltd

Thermal spraying development (TS)

www.vtt.fi/powder

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Service for introducing new material compositions to thermal

spraying from materials to performance validated product.

Powder piloting of ceramic, metallic and composite materials

including materials design

State of art selection of thermal spray techniques available in

Thermal Spray Center Finland TSCF

www.vtt.fi/powder

Thermal spraying (TS)

TSCF Thermal Spray Center Finland

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Selection of material composition meeting demands of component

operation conditions

Specification of powder characteristics in respect of spraying method

and material properties

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1

3

4

5

Material selection

and design

Powder processing,

modification and

characterization

Thermal spraying

parameters

Coating samples

spraying and testing

Pilot component

spraying

Raw materials selection

Preconditioning of the composition

Powder processing

Modification of powders to meet process demands

Powder characterization

Design of experiment (DoE) for process parameter mapping

DoE based processing parameter optimization

Online monitoring

Coating characterization

Sample preparation for coating performance tests

Application and material specific tests and analyses

Design and optimization of component spraying

Manufacturing and post treating of component

Component performance testing (lab and/or field testing)

www.vtt.fi/powder

Development steps from powder to product: Thermal spraying (TS)

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Is it possible to produce a coating to

serve in the application?

GA

TE

2.

Performance testing reveal actual

potential and need for development.

GA

TE

3.

Commercial availability of suitable

material and powder, evaluation of

tailoring possibility.

GA

TE

1.

www.vtt.fi/powder

Development steps from powder to product: Thermal spraying (TS)

2

1

3

4

5

Material selection

and design

Thermal spraying

parameters

Coating samples

spraying and testing

Pilot component

spraying

Powder processing,

modification and

characterization

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Demands and restrictions from operation conditions

Wear resistance, ductility, corrosion resistance,

grindability, polishability

Demands and restrictions of thermal spray process

Stability in spraying, melting temperature

Powder properties, flowability, particle size distribution,

dust fraction, density

Evaluation of the suitability of material and powder to

different TS processes

STEP 1. Material selection & design

TSCF Thermal Spray Center Finland www.vtt.fi/powder

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STEP 1. Material selection & design

TSCF Thermal Spray Center Finland www.vtt.fi/powder

Tailored material solutions

Wear resistance

High temperature and aqueous corrosion

resistance

Low coefficient of friction

Electrical properties

Thermal properties

Surface functionality

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Commercial powder availability with needed properties?

If not, is tailoring possible

Processing technologies

Selection of processing method based on material composition,

spraying method and desired particle size distribution

Agglomeration, gas atomization, milling, air classification, plasma

spheroidization etc.

Characterization of properties

Particle size distribution and morphology,

Chemical composition and phase structure

STEP 2. Powder processing, modification and

characterization

TSCF Thermal Spray Center Finland www.vtt.fi/powder

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Design of experiments Parameter optimization with

on-line monitoring and

process mapping

Coating

characterization

STEP 3: Thermal spraying parameters

Example of Process Map for WC-CoCr: Young

modulus against particle temperature – velocity

TSCF Thermal Spray Center Finland www.vtt.fi/powder

TS technology selection

Sample selection

Test matrix design

Sample preparation

Redesign according to

process mapping and

characterization

Modification of the powder

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Test sample spraying using optimized parameters

Residual stresses and elastic constant

Hardness, microstructure, corrosion resistance, wear

resistance, microstructure etc.

STEP 4: Coating samples spraying and testing

Online Particle diacnostics of HVOF process

TSCF Thermal Spray Center Finland www.vtt.fi/powder

1021/12/2017 10TSCF Thermal Spray Center Finland www.vtt.fi/powder

STEP 5: Pilot component spraying

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Protection against high temperature corrosion

TSCF Thermal Spray Center Finland www.vtt.fi/powder

Probe before exposure Probe after exposure

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Dispersion strengthened ceramics

Improved strength, toughness and hardness and tailored wear performance

Nano Ceramic powders

Nano oxide-oxide composite powder composition enabling amorphous coating structure

Praxair HV 2000

HVOF sprayed Al2O3-ceramic coating

Coatings for extreme conditions

HVOF spraying

Improved abrasion wear performance by using nanoSiC addition on Al2O3

TSCF Thermal Spray Center Finland www.vtt.fi/powder

Utilizing nanostructures in thermal spraying

- Ceramic coatings

0

20

40

60

80

100

120

140

160

Abra

sio

n W

ear

Resis

tance [m

g/3

0m

in]

13

02468

1012141618

Nano Sub-micron Conventional

Tailored wear performance

Conventional: carbide size 1-3 µm

Nano: carbide size 100-200 nm

Nanostructured: carbide size 1-3 µm,

crystal size 100-200 nm

a) b) c) Improved wear resistance by using sub-micron carbide

WC-CoCr -coating in fine particle wet abrasion wear

Improved cavitation resistance of tailored nano-

WC-CoCr -coating

Nano WC-powders HVOF spraying

a) Conventional carbide b) Nanocarbide

Agglomerated & sintered nano tungsten

carbide (50 nm) powder for thermal spraying

Thermico CJS HVOF

Nano WC-CoCr coating

1 µm

TSCF Thermal Spray Center Finland www.vtt.fi/powder

Coatings for extreme conditions

Utilizing nanostructures in thermal spraying

- CerMet Composite coatings

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10000150002000025000300003500040000

Parameter A Parameter B Parameter A Parameter B

Conventional Sub-micron

Volu

me L

oss-μ

m3

WC-CoCr

Weig

ht Loss –

(mg/1

20 m

in)

14TSCF Thermal Spray Center Finland

Wear

of system

Wear test

Coating properties

Applied method Spray condition ICP data

T–V plot

Powder type Porosity

Size

Material composition Cermets

Ceramics

www.vtt.fi/powder

Erosion

Adhesion

Dry abrasion

Slurry abrasion

Lamella adhesion

Coating adhesion

Stresses & Young’s Modulus

Hardness

Fracture toughness

Crack density

Feature size Phases

Porosity

HVOF

HVAF

CJS

Plasma

Shape Metals

Cold

spray

Powder production methods Gas atomization

Spray drying Plasma

spheroidization

Microstructure

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For more information

please visit our website.

Interested?

VTT Technical Research Centre of Finland Ltd

www.vtt.fi/powder

TSCF Thermal Spray Center Finland