Post on 02-Mar-2021
transcript
HVOF Thermal Spray TiC/TiB2 Coatings for AUSC Boiler/Turbine Components for
Enhanced Corrosion Protection
US DOE Project Number: DE-FE0008864Project Officer: Richard Dunst
Principal Investigator: Kanchan MondalSouthern Illinois University Carbondale
Co-Principal Investigator: Rasit KocSouthern Illinois University Carbondale
Co-Principal Investigator: Chinbay FanGas Technology Institute, Des Plaines
2016 Crosscutting Research & Rare Earth Elements Portfolios Review Apr 18-22, 2016
Presenter: Chung-Ying TsaiSouthern Illinois University Carbondale
Kanchan MondalPrincipal Investigator
Rasit KocCo-Principal Investigator
Rasit KocPowder Synthesis
Kanchan MondalParticle Characterization
Corrosion Studies
Zhezhen FuPh. D. Student
Chinbay Q FanCo-Principal Investigator
Chinbay Q. FanHVOF coating
Chung-Ying TsaiPh. D. Student
Ronald StanisResearcher
PROJECT TEAM
Adam SimsPh. D. Student
HVOF, Flame Spray Coatings
GTI project number 21397Chinbay Fan and Ronald Stanis
Background
0
10
20
30
40
50
60
0
200
400
600
800
1000
1200
Subcritical AdvancedSupercritical (270bar/600C/620C)
AUSC (350 bar/700C/720C)
AUSC with Feedwater heating
optimized
Cycl
e Ef
ficie
ncy/
CO2
Redu
ctio
n (%
)
CO2
Emiss
ions
(kg/
Mw
e-hr
)
CO2 Emissions (kg/MWe-hr)
Cycle Efficiency (% LVH)
CO2 reduction compared to subritical plants
• High Temperature, High Pressure, Supercritical water
• Mechanical Strength– Max Allowable Stress– Creep Rupture Stress– Fatigue Resistance
• Corrosion Resistance– Fireside Corrosion
• Thermal conductivity• Low coefficient of expansion• Manufacturing process issues such as
weldability and fabricability
0
50
100
150
200
250
300
450 500 550 600 650 700 750 800
Cree
p Ru
ptur
e St
ress
, Mpa
Metal Temperature, oC
Super 304H 347 HFG Sanirco 25Alloy 617 Alloy 263 Inconel 740SAVE 12 T23 T24P92
Substrate Material Class Applicable Component1 Super 304H Austenitic SH/RH tubes2 Sarnico 25 Austenitic SH/RH tubes3 HR3C Austenitic SH/RH tubes
4 STD617/CCA 617 Nickel Alloy Tubing, HP turbine-casing, piping, rotor -700 oC
5 Haynes 230 Nickel Alloy SH tubes, HP turbine rotor – 700oC
6 Inconel 740 Nickel Alloy SH tubes, HP turbine - casing, piping, rotor-760 oC
7 P91/P92 Ferritic Low Temp SH/RH
8 T91/T92 Ferritic Low Temp SH/RH, HP turbine piping –620oC
9 430 Ferritic Boiler Tubes10 T23/T24 Ferritic Furnace Tubes
Substrates of Interest
Carbothermal Process for TiC and TiB2 Powder Synthesis
100 nm
Fuel Flexible: H2, Acetylene,Kerosene…Oxidant Flexible: O2 or Air
GTI HVOF Flame Spray System
SS 304H As received After surface roughening
Water honing
Safety is first priorityHearing protectionEye protection (light)Face ShieldFlame arrestorsTwo person operation
One holding gunOne operating gas flows
Emergency Stop Button
KT3KT4
Slide 7
KT3 TiC mp 3260HVOF- up to 3300 when H2 introduced.Kyle T, 4/18/2016
KT4 Hydrogen and oxygen are mixed together and combust causing the powder material to become molten.Velocity ranges from 600-100 m/sKyle T, 4/18/2016
Flame Only
Flame with Powder
Partially Covered SamplesSpray Deposition
SS 304H C(0.04-0.1) Si(0.75) Mn (2) P (0.045) S (0.03) Cr (18-20) Ni (8-10.5)SS 430 C(0-0.12) Si (0-1) Mn (0-1) Cr(16-18) Ni(0)P91 C(0.08-0.12) Si(0.2-0.5) Mn (0.3-0.6) Mo (0.8-1.05) Cr(8-9.5) Ni(0.4 max)
62.59%0.83%34.43% 1.86% 0.29%
P91
500 µm
430
Fe OCr Mn
61.06%9.69%27.82% 1.32% 0.10%
S
500 µm
7-Days 750 ⁰C Simulated Flue Gas Corrosion Test
Pristine 430 and P91 Steels: Corrosion Behavior
430
FeO Cr S
Fe OCr SMo
20 µm
200 µm
P91
FeO Cr SMo
Pristine 430 and P91 Steels: Corrosion Behavior
7-Days 750 ⁰C Simulated Flue Gas Corrosion Test
KT1KT2
Slide 10
KT1 The surface of the steel was initially covered with Cr2O3, which was then converted to FeCr2O4, and finally Fe3O4 and Fe2O3 formed on it. These results indicated that the reason for the breakaway oxidation in type 430 stainless steel is Cr depletion beneath Cr2O3 layerand the subsequent ionisation of Fe, not the simple mechanical failure of Cr2O3.Kyle T, 4/17/2016
KT2 Hematite (Fe2O3) occurs on the inner surface of the tube. Then magnetite (Fe3O4) appears below hematite. Going deeper into the layerthere is a spinel, i.e. a mixture of magnetite and chromite.Kyle T, 4/17/2016
Fe
O
Cr
P91 Matrix
200 µm90 µm45 µm
Mo S
7-Day 750 ⁰C Simulated Flue Gas Test: P91 Substrate
Depth from Surface (µm)
Atom
ic A
mou
nt
0 430
550 ⁰C50 µm
650 ⁰C50 µm
750 ⁰C200 µm
FeO Cr S
7-Day Simulated Flue Gas Test: P91 Substrate
62.59% 0.83%34.43% 0.29%
Fe Cr SO
PristineP91
0.04%1.08%
24.94%
73.70% 0.15%
Fe Cr SO
TiBSE
Ti CoatedP91
7-Day 750 ⁰C Simulated Flue Gas Test: Ti Coated P91 Substrate
200 µm FeO Cr S
10 µm FeO Cr SMoTi
PristineP91
Ti CoatedP91
7-Day 750 ⁰C Simulated Flue Gas Test: Ti Coated P91 Substrate
CrSMo
Ti Fe
O
0 49
Ti Coating P91 Matrix28 µm ~4 µm
7-Day 750 ⁰C Simulated Flue Gas Test: Ti Coated P91 Substrate
Depth from Surface (µm)
Atom
ic A
mou
nt
Pristine P91
7-Day 700 ⁰C H2O + O2 Corrosion Test on P91 Substrates
30 µm
30 µmFeO CrTi
Ti Coated P91
FeO Cr
7-Day 700 ⁰C Air Corrosion Test on P91 Substrates
Pristine P91
50 µm
Ti Coated P91
10 µm FeO CrTi
FeO Cr
XRD Results of Ti Coated and Pristine P91 After Corrosion Tests
H2O + O2
Sim Flue Gas
Ti Coated-Sim Flue Gas
O2
◊ ◊ ◊◊ ◊ ◊ ◊
XX
Inte
nsity
Δ Δ ΔΔΔΔ
ΔΔΔ
Δ Δ
◊ ◊◊ ◊ ◊ ◊ ◊
◊ ◊ ◊ ◊ ◊ ◊ ◊
Δ- Rutile ◊- Hematite X- Fe-Cr
Impact of Coating Density on Corrosion Resistant
10 µm FeO Cr SMoTi
50 µm FeO Cr SMoTi
Dense Coating
LooseCoating
Ti MetalCoated
TiCCoated In
tens
ity
ΔΔ
ΔΔΔ
Δ
ΔΔ
ΔΔ
Δ
10 µm
Ti MetalCoated
10 µm
TiCCoated
BSE Ti Fe
BSE Ti Fe
Δ- Rutile
HVOF Coatings: TiC and Ti Metal
Achievements
HVOF thermal spray coating of the prepared powders on P91 steel substrates.
Corrosion characterizations of pristine and coated P91 steels.
Increased longevity and corrosion resistance of the coated substrates subjected to fireside corrosion in AUSC SH/RH tubes and boiler tubes.
Acknowledgement
Thank You
US DOE Project Number: DE-FE0008864Project Officer: Richard Dunst