vtt powder piloting service: thermal spraying development (ts)
TRANSCRIPT
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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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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)
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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
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20
40
60
80
100
120
140
160
Abra
sio
n W
ear
Resis
tance [m
g/3
0m
in]
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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