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© Fraunhofer UMSICHT
Fraunhofer UMSICHT
Institutsteil Sulzbach-Rosenberg – Sommersymposium am 27. Juni 2013
Dr. HDR Patrick J. Masset
Hochtemperaturanwendungen Herausforderungen für Beschichtungstechnologien
© Fraunhofer UMSICHT
Folie 2
Agenda
1. Energy situation
2. Challenges for materials for power engineering
3. Coatings as alternative
4. Conclusion / outlook
© Fraunhofer UMSICHT
Folie 3
Technologic developments
Foto: DIHK
© Fraunhofer UMSICHT
Folie 4
Evolution of the world population
Estimated world population, 1950-2000, and projections: 2000-2050
Source: UN World Population to 2300
© Fraunhofer UMSICHT
Folie 5
Evolution of the energy needs
The combined increase of the individual / industrial needs and population growth leads
to high requirements for power engineering within a short time
Global energy demand rises by over one third in the period to 2035, underpinned by rising living standards in China, India & the Middle East
Source: OECD/IEA 2012
© Fraunhofer UMSICHT
Folie 6
Agenda
1. Energy situation
2. Challenges for materials for power engineering
3. Coatings as alternative
4. Conclusion / outlook
© Fraunhofer UMSICHT
Folie 7
Materials and power engineering
Applications
− Mining
− Materials processing
− Production, transport
− Conversion processes
Large variety of “raw materials”
− Coal, fuels, biomass, wastes, ores
− Sun, wind, hydraulic
Economy
− Geographic and geopolitical aspects
− Cost, availability
© Fraunhofer UMSICHT
Folie 8
Costs of corrosion
− All economic sectors
− 4% of GDP
− Consumption of raw materials
− Safety and environmental issues
Combined loads
− Thermal, chemical, mechanical, radiation
− Gaseous, liquid, solid phases
− High temperatures, pressures
Challenges for coatings for power engineering
© Fraunhofer UMSICHT
Folie 9
Agenda
1. Energy situation
2. Challenges for materials for power engineering
3. Coatings as alternative
4. Conclusion / outlook
© Fraunhofer UMSICHT
Folie 10
Why coatings are so interesting?
Technologies: electrochemistry, PVD, CVD, thermal spraying, laser cladding
Complementary properties to bulk properties
Low cost compared to bulk materials (low thickness)
Composition and / or properties on request
Often reparable
Combination of properties (corrosion / wear)
molding process
light alloys (TiAl)
© Fraunhofer UMSICHT
Folie 11
Chemical densification of thermal sprayed oxide coatings
4% HCl, 700 °C, 3d
100 µm
2% HCl, 800 °C, 1d
2% HCl, 600 °C, 3d 2% HCl, 800 °C, 3d
0% HCl, 700 °C, 3d
YSZ
NiCr-alloy
2% HCl, 700 °C, 3d
100 µm 100 µm
100 µm 100 µm 100 µm
Densification front from the oxide / alloy interface outwards
Densification process depends on temperature and solvo-thermal parameters
© Fraunhofer UMSICHT
Folie 12
treated
untreated
Tribological properties
Reduction of the friction coefficient
Improvement of the tribological properties
Cycles Fr
icti
on
co
effi
cien
t µ
Line scan
Untreated Treated
© Fraunhofer UMSICHT
Folie 13
Porosity and hardness
Decrease of the residual porosity after solvo-thermal post-treatment
Increase of the hardness of the coating
Temperature (°C) Temperature (°C) untreated untreated
Poro
sity
(%
)
Har
dn
ess
HV
© Fraunhofer UMSICHT
Folie 14
Resistance to mechanical impacts
Better resistance to impacts, reduced formation of cracks
Improvement of the oxide layer cohesion
trace of scratch test
200 µm
200 µm
© Fraunhofer UMSICHT
Folie 15
Adhesion properties
Increase of the adhesion of the Top-Coat to the Bond-Coat
© Fraunhofer UMSICHT
Folie 16
Resistance to thermal shocks
Cycles in liquid Al 4 min in the melt at 800°C 1 min cooling in air till 420 °C
420°C 800°C
800
C 20
C
Steel 1.2343
met./cer. composite
ZrO2 on Ni-based bond-coat +solvothermal
Cycles
cer./cer. composite on Ni-based Bond-coat
MgO + Al2O3-TiO2
Improvement of the chemical stability vs. liquid metals
Increased resistance against thermal shocks Cycles in air 20 min at 800°C 40 min cooling in air till 20 °C
© Fraunhofer UMSICHT
Folie 17
TiAl alloys: evidence of environmental embrittlement
Accelerated oxidation
100h in air at 600 °C
100h in air at 900 °C
5 µm
5 µm
Accelerated embrittlement
100 h, air
Accelerated oxidation of TiAl above 700 °C
Significant ductility loss (environmental embrittlement)
Decrease of mechanical properties (strength)
© Fraunhofer UMSICHT
Folie 18
Thermal spraying techniques 0 – 45 µm
45 – 63 µm
63 – 90 µm
32 – 45 µm15 – 32 µm
Example of thermal spraying process. Powder size < 45 µm
High velocity spraying of molten metallic powder. Powder composition: Ti-51Al-2Cr-2Nb and Ti-54Al-2Cr-2Nb
FhG
© Fraunhofer UMSICHT
Folie 19
Coated samples
1 cm
MO-CVD PVD HVOF
Source: Report project IGF-Nr. 24 EBG
© Fraunhofer UMSICHT
Folie 20
Coating of industrial components
TNB + Al-CVD oxidised 50 h at 1 100 °C
+ F
TNB + Al-CVD + F oxidised 100 h at 900 °C
Al2O3
TNB + Al-CVD + F oxidised 50 h at 1 100 °C
Al2O3
TNB + Al-CVD oxidised 100 h at 900 °C
Al2O3
TiO2
Blades TNB alloy (as received)
TNB + Al-CVD (0.5 – 1 µm)
Oxidation protection up to 1 100 °C + improved mechanical resistance (coating)
Applicability of the CVD route on technical parts
Untreated blades do not withstand oxidation tests
Source: Report project IGF-Nr. 24 EBG
© Fraunhofer UMSICHT
Folie 21
Improvement of the mechanical properties
×2
×2
×3
Goal
Higher ductility
Hig
her
stre
ng
th
90%
Halogen effect
no protection
Source: Report project IGF-Nr. 24 EBG
© Fraunhofer UMSICHT
Folie 22
Mechanical properties: overview
Source: P. Masset et al, Oral communication, ECS Fall Meeting, Honolulu (Oct. 2012)
© Fraunhofer UMSICHT
Folie 23
Agenda
1. Energy situation
2. Challenges for materials for power engineering
3. Coatings as alternative
4. Conclusion / outlook
© Fraunhofer UMSICHT
Folie 24
Conclusion
Suitable protection even under complex loads and / or environments
Economic benefit
Coating development specific to the applications
Meet challenges of power engineering
© Fraunhofer UMSICHT
Folie 25
Outlook
Nano-materials
− Lower thickness of coatings
− Less materials
− Specific properties (catalysis)
Interdisciplinary approach
− Combination of technologies
− Be inspired by other applications / disciplines
Versatile technologies
− Adaptable coatings for different applications
− Family of coatings
© Fraunhofer UMSICHT
Folie 26
FRAUNHOFER UMSICHT
Vielen Dank für Ihre Aufmerksamkeit! Thank you for your attention! Merci de votre attention!
Institutsteil Sulzbach-Rosenberg
Kontakt Fraunhofer UMSICHT Fraunhofer-Institut für Umwelt-, Sicherheits- und Energietechnik UMSICHT Institutsteil Sulzbach-Rosenberg Dr. HDR Patrick J. Masset E-Mail: [email protected] Telefon: 09661-908 472 Internet: http://www.umsicht-suro.fraunhofer.de E-Mail: [email protected]