Materials and Structures for Aerospace Propulsion Systems ...
Materials and Structures for Aerospace Propulsion Systems ...
Materials and Structures for Aerospace Propulsion Systems ...
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<strong>Materials</strong> <strong>and</strong> <strong>Structures</strong> <strong>for</strong> <strong>Aerospace</strong><br />
<strong>Propulsion</strong> <strong>Systems</strong>
Scramjets<br />
Rocket<br />
X-43b<br />
Aeroturbine<br />
Image courtesy of ATK
High By-pass Aeroturbine
Air flow<br />
http://www.aip.org/tip/INPHFA/vol-10/iss-4/p24.html<br />
Scramjets integrate air <strong>and</strong> space by Dean Andreadis
Efficiency of Various <strong>Propulsion</strong> Cycles:<br />
Specific Impulse (Thrust/weight)<br />
8000<br />
Hydrogen Fuel<br />
Hydrocarbon Fuels<br />
I sp<br />
6000<br />
4000<br />
Turbojets<br />
Ramjets<br />
Rocket<br />
RBCC<br />
TBCC<br />
2000<br />
Turbojets<br />
Ramjets<br />
Scramjets<br />
Scramjets<br />
Rockets<br />
0<br />
0 10 20<br />
MACH NUMBER
Specific Fuel Consumption <strong>for</strong> Various Concepts<br />
10<br />
9<br />
Conventional Rocket<br />
8<br />
7<br />
TSFC (Lbm/Lbf/Hr.)<br />
6<br />
5<br />
4<br />
3<br />
Turbine Engines<br />
Ramjet Take Over<br />
Scram/Rocket<br />
Rocket Off<br />
2<br />
1<br />
Ram/Scram Operation<br />
0<br />
0 1 2 3 4 5 6 7 8 9 10 11 12<br />
Hydrogen Fuel<br />
Flight Mach Number
Fuel Efficiency In the Aero-turbine Industry:<br />
JT3C<br />
Turbojet<br />
Low Bypass<br />
Turbofan<br />
High Bypass<br />
Turbofan<br />
2 nd Gen High Bypass<br />
Turbofan<br />
JT3D-1<br />
CJ805<br />
JT8D-9<br />
Specific Fuel<br />
consumption<br />
JT9D-7A<br />
JT8D-217<br />
TAY 620<br />
JT9D-3A<br />
CFM56-2<br />
CF6-6D RB-211-524D<br />
V2500 A1 CFM56-5A<br />
BR 715<br />
JT9D-7R4G2<br />
CF6-80A RB-211-535E4 CF6-80C2-B6F<br />
PW2037<br />
CFM56-5C4<br />
PW4056<br />
CF6-80E1-A2<br />
PW4168 PW4098<br />
PW4084<br />
TRENT 895<br />
GE90-85B<br />
GE90-115B<br />
R. SHAFRICK, GE Aircraft Engines<br />
1950 1960 1970 1980 1990 2000 2010 2020<br />
Certification Date
Engine Temperature Trend<br />
GE90-115B<br />
Gas Temperature, FRT<br />
TF33<br />
CF6-50E<br />
CFM56-5C4 GE90-90B<br />
CFM56-5B<br />
Trent 772<br />
CFM56-5C2<br />
GE90-94B<br />
Trent 892<br />
Trent 556<br />
PW 4090<br />
CF34-10<br />
V2533 CFM56-7B<br />
CFM56-3C<br />
PW 6024<br />
BR 715<br />
CF6-50E2 PW 2037<br />
CF6-80E1<br />
CF6-80C2A5 PW 4062<br />
CF34-8C1<br />
CF6-80A3<br />
CFM56-2B<br />
CF6-80C2D1F<br />
CFM56-5A<br />
BR 710<br />
CF6-80C2B1F<br />
JT9D<br />
CF34-3A<br />
CF34-3B<br />
CFM56-3B2<br />
CF6-80C2A1<br />
CFM56-3B1<br />
JT8D-219<br />
RB 211<br />
62 64 66 68 70 72 74 76 78 80 82 84 86 88 90 92 94 96 98 00 02 04 06 08 10 12<br />
Engine Certification Date
Role of Airfoil <strong>Materials</strong><br />
CMCs<br />
Increased<br />
Temperature<br />
Capability(K)<br />
1600<br />
1300<br />
1000<br />
GEN2<br />
GEN1<br />
Advanced Thermal Barrier <strong>Systems</strong><br />
GEN3<br />
GEN4<br />
Superalloys<br />
1985 1990 1995 2000 2005<br />
Introduction Date<br />
Turbine Airfoil Material Advancements
Specific Strengths of Metallic <strong>Systems</strong><br />
Superalloys &<br />
Refractories
More High Temperature <strong>Materials</strong>
Role of Airfoil <strong>Materials</strong><br />
CMCs<br />
Increased<br />
Temperature<br />
Capability(K)<br />
1600<br />
1300<br />
1000<br />
GEN2<br />
GEN1<br />
Advanced Thermal Barrier <strong>Systems</strong><br />
GEN3<br />
GEN4<br />
Superalloys<br />
1985 1990 1995 2000 2005<br />
Introduction Date<br />
Turbine Airfoil Material Advancements
Superalloy Turbine Air Foils<br />
Equiaxed (EQ) Dir. Sol. (DS) Single Xtal (SX)
Ni Superalloy Improvements<br />
1020<br />
Temperature Capability - °C<br />
1000<br />
980<br />
960<br />
940<br />
920<br />
900<br />
880<br />
Ρ80<br />
Ρ125<br />
Ρ80Η<br />
Ν4<br />
Ρ142<br />
Ν5<br />
Ν6<br />
ΜΞ4<br />
860<br />
840<br />
1969 1972 1982 1984 1988 1989 1994<br />
Year of Introduction<br />
2000<br />
ASM-TMS NY042198 16
Modeling at the scale of the grains<br />
Single crystal turbine<br />
blade
Role of Airfoil <strong>Materials</strong><br />
CMCs<br />
Increased<br />
Temperature<br />
Capability(K)<br />
1600<br />
1300<br />
1000<br />
GEN2<br />
GEN1<br />
Advanced Thermal Barrier <strong>Systems</strong><br />
GEN3<br />
GEN4<br />
Superalloys<br />
1985 1990 1995 2000 2005<br />
Introduction Date<br />
Turbine Airfoil Material Advancements
Airfoil Technology<br />
Airfoil Technology<br />
Heat<br />
Transfer<br />
High Per<strong>for</strong>mance Coating <strong>Systems</strong>:<br />
Enabling technology <strong>for</strong> advanced gas turbines
Transverse Section
Al Reservoir<br />
Thermal Barrier Multilayer
Nanoscale Porosity
Deposition Effects on Microstructure<br />
Deposition Effects on Microstructure<br />
Airfoil Mode<br />
Plat<strong>for</strong>m Mode
Interplay with<br />
Component<br />
Geometry<br />
20 µm<br />
• Reduced coating thickness within recess,<br />
quantitatively consistent with reduction<br />
in integrated flux due to shadowing by<br />
corners.<br />
• Reduced inter-columnar gap width—<strong>and</strong><br />
increased propensity to sintering—due<br />
to elimination of most oblique vapor flux.<br />
2 µm<br />
5 µm
Role of Airfoil <strong>Materials</strong><br />
CMCs<br />
Increased<br />
Temperature<br />
Capability(K)<br />
1600<br />
1300<br />
1000<br />
GEN2<br />
GEN1<br />
Advanced Thermal Barrier <strong>Systems</strong><br />
GEN3<br />
GEN4<br />
Superalloys<br />
1985 1990 1995 2000 2005<br />
Introduction Date<br />
Turbine Airfoil Material Advancements
Ceramic Matrix Composites (CMC)<br />
CMC Combustor Liner<br />
Cooling Air Reduction<br />
Weight Reduction<br />
20% NOx Reduction<br />
CMC Vane<br />
CMC Blade<br />
Weight Reduction<br />
Reduced Cooling Air<br />
Increased Efficiency<br />
CMC’s Reduce Weight <strong>and</strong> Improve Per<strong>for</strong>mance
(MI) SiC/SiC (DENSE MATRIX)<br />
T = 1400C (Metals < 1100C)<br />
‣High Thermal Conductivity<br />
‣Inter-laminar Shear Strength<br />
‣Reduced Sensitivity to Pesting
Transition duct<br />
Nozzles<br />
Integrally woven<br />
CMC <strong>Structures</strong><br />
Alumina anchor tube in<br />
CMC skin <strong>for</strong> pin joint<br />
Braided SiC/SiC<br />
Hyper-Therm Inc.<br />
Metallic struts<br />
with CMC skin
Angle Interlock<br />
Sylramic/SiC<br />
±45°
CMC Combustor<br />
Liners<br />
<br />
<br />
<br />
<br />
Hi-Nicalon, Slurry Cast<br />
Successful Engine Testing<br />
Pre <strong>and</strong> Post Engine Test NDE<br />
Revealed Degradation<br />
Additional Engine Testing<br />
CMC Inner Combustor Liner After Engine Testing<br />
CMC Combustor Liner Rig & Engine Testing Successful
CMC Applications in Utility Gas Turbines<br />
Benefits:<br />
• NOx reductions (50%)<br />
• CO reductions (50%)<br />
• Improved stability<br />
• Life improvement<br />
Annular Combustors<br />
Shroud<br />
Segments<br />
Benefits:<br />
• 90% cooling air reduction<br />
• 0.2% efficiency gain<br />
• Reduced tip clearance<br />
These efficiency,<br />
power, <strong>and</strong> emissions<br />
benefits translate to<br />
$M in annual savings<br />
<strong>for</strong> each installation.<br />
Benefits:<br />
• >90% cooling air reduction<br />
• 0.4% efficiency gain<br />
• Cost savings over SOA technology<br />
Vanes<br />
Benefits:<br />
• 90% cooling air reduction<br />
• Efficiency gains of >1%<br />
• NOx reductions (50%)
Hybrid CMC Concept<br />
The "hybrid" concept involves use of a moderate temperature (~1100° -<br />
1200°C) CMC structural member bonded to a ceramic insulating material<br />
having good stability at 1600°C <strong>and</strong> good erosion resistance.<br />
Hot Face Temp<br />
1600°C<br />
Ceramic<br />
Adhesive<br />
Bond Line<br />
Temp.<br />
1100°C<br />
FGI Insulation Layer<br />
Structural CMC<br />
~3mm<br />
~4mm<br />
Cold Face Temp<br />
750°C<br />
• Oxide fiber available<br />
• Insulating material technology available<br />
• Reduces cooling needs drastically
Role of Airfoil <strong>Materials</strong><br />
SiC/SiC CMCs<br />
Increased<br />
Temperature<br />
Capability(K)<br />
1600<br />
1300<br />
1000<br />
GEN2<br />
GEN1<br />
Advanced Thermal Barrier <strong>Systems</strong><br />
GEN3<br />
GEN4<br />
Superalloys<br />
1985 1990 1995 2000 2005<br />
Introduction Date<br />
Turbine Airfoil Material Advancements
Thermal Barrier Multilayer:<br />
Challenging Thermo-Chemo-Mechanical System
Thermal Property Interplay
RESIDUAL STRESS IN TGO
Thermal Property Interplay<br />
Slide 24
Thermal Barrier Multilayer:<br />
Challenging Thermo-Chemo-Mechanical System
YSZ Compatibility with TGO<br />
YSZ Compatibility with TGO<br />
EB-PVD on FeCrAlY substrate<br />
1200°C<br />
TGO<br />
TGO<br />
Zirconate<br />
reactive<br />
with TGO<br />
Limit of thermochemical<br />
compatibility ~21%YO 1.5<br />
After As Deposited 100h at 1200°C<br />
7YSZ compatible with TGO<br />
(no inter-phases <strong>for</strong>med)<br />
1 µm
Degradation Modes In Engines<br />
Delay Spalling By Underst<strong>and</strong>ing<br />
Mechanisms<br />
And Adjusting Constituent<br />
Properties<br />
80%<br />
Impact<br />
Damage<br />
TBC spallation<br />
TBC<br />
spallation<br />
40%<br />
1820 engine cycles
Step I:Identify All Mechanisms Limiting Durability<br />
Step I:Identify All Mechanisms Limiting Durability<br />
Step II: Develop Models that Relate Durability to Material Properties
Example I (Intrinisc): Failure by TGO Rumpling<br />
Example I (Intrinisc): Failure by TGO Rumpling<br />
• Strain misfits cause cyclic<br />
stresses that motivate<br />
cycle-by-cycle crack<br />
growth in TBC<br />
• Highly non-linear:<br />
. Requires numerical code<br />
• Phenomena include TGO<br />
lateral growth, thermal<br />
expansion misfit<br />
(martensite), cyclic<br />
plasticity.<br />
Swelling<br />
Martensite
Fails at Oxide/Oxide Interface<br />
LARGE SCALE BUCKLE: THE END OF LIFE<br />
•WHAT HAPPENED EARLIER?
DISPLACEMENT INSTABILITY<br />
Multi-Parameter Phenomenon:<br />
Relevant Phenomena:<br />
•Elongation/Thickening of TGO<br />
•Plastic Flow of Bond Coat<br />
•Strain Misfit of Bond Coat<br />
Need Model<br />
Plus<br />
Critical Experiments<br />
DESCRIBE CONJOINTLY
OBJECTIVE: DEVISE MECHANISM MAPS THAT SPECIFY SALIENT<br />
NON-DIMENSIONAL PARAMETERS
UNDERSTAND THE FUNDAMENTALS<br />
TGO
De<strong>for</strong>mation Mechanism Map<br />
Synchotron Measurements
Synchotron Measurements
•Thermal Expansion<br />
•Martensite<br />
•Swelling<br />
‣ “Soften” Bond Coat
STRAIN MISFITS: MARTENSITE TRANSFORMATION<br />
L1 0<br />
600C<br />
41 42 43 44 45 46 47 48 49<br />
B2<br />
650C<br />
41 42 43 44 45 46 47 48 49
VALIDATION Model EXPERIMENTS: Validation: Example AN EXAMPLE<br />
1. Elastic properties of constituents<br />
2. Thermal expansion mismatch between layers.<br />
3. Power-law creep.<br />
4. Reversible phase trans<strong>for</strong>mation in bond coat.<br />
5. Growth stress in TGO.<br />
6. Thickening <strong>and</strong> lateral growth strain in the TGO<br />
7. Initial Interface Imperfections
ANIMATION OF TGO DISTORTION AND ELONGATION<br />
QuickTime <strong>and</strong> a<br />
GIF decompressor<br />
are needed to see this picture.
Model<br />
Validation:<br />
Transition<br />
to GE<br />
Balint-Hutchinson Code<br />
TGO<br />
BC<br />
Substrate<br />
Code now in use at GE
SENSITIVITY STUDY USING MECHANISM MAP:<br />
CAN MECHANISM BE SUPPRESSED?
USE MECHANISM MAP TO ELIMINATE RATCHETING<br />
Interface Toughness<br />
Becomes Key<br />
Parameter:
NEW INTERFACE<br />
TOUGHNESS TEST<br />
G side<br />
= 1 2 S ⎛ π δ⎞<br />
⎝ 4 b⎠<br />
4<br />
⎛<br />
+2D π ⎞<br />
⎝ b⎠<br />
2 π<br />
⎛ δ⎞<br />
⎝ 4 b⎠<br />
2<br />
f=0.26<br />
f=1.0<br />
Γ = 20Jm -2
Mode I Adhesion Energy<br />
of Metal / Alumina Interfaces
Work of Separation: Ni/Al 2 O 3 interfaces<br />
Expt.<br />
TBC Ni(Al)/Al 2 O 3 interface:<br />
Fracture at interface<br />
Mode I toughness ~ 20 J/m 2<br />
Pure Ni/Al 2 O 3 interface:<br />
Fracture in Alumina<br />
Mode I toughness > 300 J/m 2<br />
Theo.<br />
3.79 J/m 2<br />
6.84 J/m 2 3.25 J/m 2<br />
1.30J/m 2 Al-termination O-termination
Delay Spalling<br />
By Underst<strong>and</strong>ing<br />
Mechanisms<br />
And<br />
Adjusting Constituent<br />
Properties<br />
Failure Modes After Engine Test
Two Basic Erosion <strong>and</strong> FOD Mechanisms<br />
Two Basic Erosion <strong>and</strong> FOD Mechanisms<br />
I:Elastodynamic<br />
50µm<br />
II:Viscoplastic<br />
50µm
Viscoplastic Domain<br />
QuickTime <strong>and</strong> a<br />
BMP decompressor<br />
are needed to see this picture.<br />
4<br />
LE Simulations<br />
Soft at High Temperature
Erosion Threshold Map<br />
Erosion Threshold Map<br />
ELASTO-<br />
DYNAMIC<br />
DOMAIN<br />
Identify Importance of<br />
Material Properties:<br />
‣High Toughness<br />
‣Soft at High Temperature
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