Abstract

Foreign object damage (FOD) and attack by calcium–magnesium–aluminosilicates (CMAS) have been identified as two key damage and failure mechanisms in environmental barrier coatings (EBCs), which are being developed as an enabling technology for silicon carbide (SiC) based composites in gas turbine engines. CMAS exposure at elevated temperatures has been shown to cause premature failure in ytterbium disilicate (Yb2Si2O7) based EBCs. Previously, the effects of foreign object damage were studied on NASA's Yb2Si2O7-based EBC deposited on SiC. This study aims to understand the synergistic effects of CMAS attack and FOD on the same EBC system. CMAS was loaded onto the EBC at either 2 mg/cm2 or 4 mg/cm2 prior to being fully reacted for 4 h in a 1316 °C furnace. Samples were then impacted at room temperature using a 1.59 mm hardened steel ball with projectile velocities of 50–100 m/s. The impact damage was characterized by depth of the impact crater and length of the EBC delamination as determined by optical profilometry and scanning electron microscopy (SEM) of the cross-sectioned samples. The results of the samples subjected to CMAS attack were then compared to that of the previous study on NASA's baseline Yb2Si2O7-based EBC. A mechanical assessment of the coatings was also made. Vickers indentation was used to determine coating hardness as well as estimate indentation fracture toughness, and nano-indentation was used to estimate the Young's modulus.

References

1.
Smialek
,
J.
,
Robinson
,
C.
,
Opila
,
E.
,
Fox
,
D.
, and
Jacobson
,
N.
,
1999
, “
SiC and Si3N4 Recession Due to SiO2 Scale Volatility Under Combustor Conditions
,”
Adv. Compos. Mater.
,
8
(
1
), pp.
33
45
.10.1163/156855199X00056
2.
Opila
,
E.
,
Smialek
,
J.
,
Robinson
,
C.
,
Fox
,
D.
, and
Jacobson
,
N.
,
1999
, “
SiC Recession Caused by SiO2 Scale Volatility Under Combustion Conditions: II, Thermodynamics and Gaseous-Diffusion Model
,”
J. Am. Ceram. Soc.
,
82
(
7
), pp.
1826
1834
.10.1111/j.1151-2916.1999.tb02005.x
3.
Jacobson
,
N.
,
1993
, “
Corrosion of Silicon-Based Ceramics in Combustion Environments
,”
J. Am. Ceram. Soc.
,
76
(
1
), pp.
3
28
.10.1111/j.1151-2916.1993.tb03684.x
4.
Jacobson
,
N.
,
Fox
,
D.
,
Smialek
,
J.
,
Opila
,
E.
, and
Robinson
,
C.
,
2005
, “
Performance of Ceramics in Severe Environments
,”
ASM International
, 13, pp.
565
–5
78
.10.31399/asm.hb.v13b.a0003842
5.
Lee
,
K.
,
Fox
,
D.
,
Eldridge
,
J.
,
Zhu
,
D.
,
Robinson
,
C.
,
Bansal
,
N.
, and
Miller
,
R.
,
2003
, “
Upper Temperature Limit of Environmental Barrier Coatings Based on Mullite and BSAS
,”
J. Am. Ceram. Soc.
,
86
(
8
), pp.
1299
1306
.10.1111/j.1151-2916.2003.tb03466.x
6.
Lee
,
K.
,
Fox
,
D.
, and
Bansal
,
N.
,
2005
, “
Rare Earth Silicate Environmental Barrier Coatings for SiC/SiC Composites and Si3N4 Ceramics
,”
J. Eur. Ceram. Soc.
,
25
(
10
), pp.
1705
1715
.10.1016/j.jeurceramsoc.2004.12.013
7.
Bhatt
,
R.
,
Choi
,
S.
,
Cosgriff
,
L.
,
Fox
,
D.
, and
Lee
,
K.
,
2008
, “
Impact Resistance of EBC Coated SiC/SiC CMCs
,”
J. Mater. Sci. Eng. A
,
476
, pp.
8
19
.10.1016/j.msea.2007.04.067
8.
Choi
,
S.
,
2015
, “
Foreign Object Damage in Ceramic Matrix Composites
,”
Ceramic Matrix Composites: Materials, Modelling, and Technology
, American Ceramic Society, John Wiley and Sons, Hoboken, NJ, pp.
405
429
.https://onlinelibrary.wiley.com/doi/pdf/10.1002/9781118832998.ch14
9.
Hoffman
,
L.
,
Presby
,
M.
,
Harder
,
B.
,
Stokes
,
J.
, and
Salem
,
J.
,
2023
, “
The Effect of Oxidation in Environmental Barrier Coatings Subject to Foreign Object Damage
,”
ASME
Paper No. SSDM2023-107437.10.1115/SSDM2023-107437
10.
Choi
,
S.
,
Wright
,
J.
,
Faucett
,
C.
, and
Ayre
,
M.
,
2014
, “
Phenomena of Foreign Object Damage by Spherical Projectiles in EB-PVD Thermal Barrier Coatings of Turbine Airfoils
,”
ASME J. Eng. Gas Turbines Power
,
136
, p.
102603
.10.1115/1.4027362
11.
Kedir
,
N.
,
Garcia
,
E.
,
Kirk
,
C.
,
Guo
,
Z.
,
Gao
,
J.
,
Zhai
,
X.
,
Sun
,
T.
,
Fezzaa
,
K.
,
Sampath
,
S.
, and
Chen
,
W. W.
,
2020
, “
In-Situ Characterization of Foreign Object Damage in Environmental Barrier Coated Silicon Carbide
,”
J. Am. Ceram. Soc.
,
103
(
8
), pp.
4586
4601
.10.1111/jace.17165
12.
Choi
,
S.
, and
Racz
,
Z.
,
2012
, “
Effects of Target Size on Foreign Object Damage in Gas-Turbine Grade Silicon Nitrides by Steel Ball Projectiles
,”
ASME J. Eng. Gas Turbines Power
,
134
(
5
), p.
051301
.10.1115/1.4004738
13.
Presby
,
M. J.
,
Mansour
,
R.
,
Manigandan
,
K.
,
Morscher
,
G. N.
,
Abdi
,
F.
,
Godines
,
C.
,
Eftekharian
,
A.
, and
Choi
,
S. R.
,
2019
, “
Characterization and Simulation of Foreign Object Damage in Curved and Flat SiC/SiC Ceramic Matrix Composites
,”
Ceram. Int.
,
45
(
2
), pp.
2635
2643
.10.1016/j.ceramint.2018.10.207
14.
Kedir
,
N.
,
Garcia
,
E.
, and
Kirk
,
C.
,
2021
, “
Impact Damage of Narrow Silicon Carbide (SiC) Ceramics With and Without Environmental Barrier Coatings (EBCs) by Various Foreign Object Debris (FOD) Simulants
,”
Surf. Coat. Technol.
,
407
, p.
126779
.10.1016/j.surfcoat.2020.126779
15.
Hoffman
,
L.
,
Presby
,
M.
,
Stokes
,
J.
, and
Harder
,
B.
,
2024
, “
Foreign Object Damage in Ytterbium Disilicate Based Environmental Barrier Coatings Modified for Oxidation Resistance
,”
ASME
Paper No. SSDM2024-121869.10.1115/SSDM2024-121869
16.
Smialek
,
J.
,
1991
, “
The Chemistry of Saudi Arabian Sand: A Deposition Problem on Helicopter Turbine Airfoils
,” NASA, Cleveland, OH, NASA Technical Memorandum 105234.
17.
Shifler
,
D.
, and
Choi
,
S.
,
2018
, “
CMAS Effects on Ship Gas-Turbine Components/Materials
,”
ASME
Paper No. GT2018-75865.10.1115/GT2018-75865
18.
Stokes
,
J.
,
Harder
,
B.
,
Wiesner
,
V.
, and
Wolfe
,
D.
,
2019
, “
High-Temperature Thermochemical Interactions of Molten Silicates With Yb2Si2O7 and Y2Si2O7 Environmental Barrier Coating Materials
,”
J. Eur. Ceram. Soc.
,
39
(
15
), pp.
5059
5067
.10.1016/j.jeurceramsoc.2019.06.051
19.
Stokes
,
J.
,
Presby
,
M.
,
Webster
,
R.
,
Setlock
,
J.
, and
Harder
,
B.
,
2023
, “
Thermochemical/Thermomechanical Synergies in High-Temperature Solid Particle Erosion of CMAS-Exposed EBCs
,”
ASME
Paper No. GT2023-101212.10.1115/GT2023-101212
20.
Martin
,
D.
,
Romero
,
A.
,
Wellman
,
R.
, and
Hussain
,
T.
,
2022
, “
Interaction of CMAS on Thermal Sprayed Ytterbium Disilicate Environmental Barrier Coatings: A Story of Porosity
,”
Ceram. Int.
,
48
(
6
), pp.
8286
8296
.10.1016/j.ceramint.2021.12.033
21.
Stokes
,
J.
,
Harder
,
B.
,
Wiesner
,
V.
, and
Wolfe
,
D.
,
2021
, “
Melting and Crystallization Behavior of CaO-MgO-Al2O3-SiO2 Silicates Relevant to Turbine Engine Applications
,” NASA, Cleveland, OH, NASA Technical Memorandum 20210020388.
22.
ISO
,
2018
, “
Metallic Materials—Vickers Hardness Test Part 1: Test Method
,” International Organization for Standardization, Geneva, Switzerland, Standard No. ISO 6507.
23.
Lawn
,
B.
,
Evans
,
A.
, and
Marshall
,
D.
,
1980
, “
Elastic/Plastic Indentation Damage in Ceramics: The Median Radial Crack System
,”
J. Am. Ceram. Soc.
,
63
, pp.
574
581
.10.1111/j.1151-2916.1980.tb10768.x
24.
Marshall
,
D.
,
Lawn
,
B.
, and
Evans
,
A.
,
1982
, “
Elastic/Plastic Indentation Damage in Ceramics: The Lateral Crack System
,”
J. Am. Ceram. Soc.
,
65
(
11
), pp.
561
566
.10.1111/j.1151-2916.1982.tb10782.x
25.
Quinn
,
G. D.
, and
Bradt
,
R. C.
,
2007
, “
On the Vickers Indentation Fracture Toughness Test
,”
J. Am. Ceram. Soc.
,
90
(
3
), pp.
673
680
.10.1111/j.1551-2916.2006.01482.x
26.
Oliver
,
W. C.
, and
Pharr
,
G. M.
,
1992
, “
An Improved Technique for Determining Hardness and Elastic Modulus Using Load and Displacement Sensing Indentation Experiments
,”
J. Mater. Res.
,
7
(
6
), pp.
1564
1583
.10.1557/JMR.1992.1564
27.
Richards
,
B. T.
,
Young
,
K. A.
,
De Francqueville
,
F.
,
Sehr
,
S.
,
Begley
,
M. R.
, and
Wadley
,
H. N.
,
2016
, “
Response of Ytterbium Disilicate–Silicon Environmental Barrier Coatings to Thermal Cycling in Water Vapor
,”
Acta Mater.
,
106
, pp.
1
14
.10.1016/j.actamat.2015.12.053
28.
Smolin
,
Y. I.
, and
Shepelev
,
Y. F.
,
1970
, “
The Crystal Structures of the Rare Earth Pyrosilicates
,”
Acta Crystallographica Section B Structural Crystallography and Crystal Chemistry
,
26
(
5
), pp.
484
492
.10.1107/S0567740870002698
29.
Fedorov
,
N.
,
Andreev
,
I.
, and
Meliksetyan
,
N.
,
1975
, “
Preparation and Properties of Single Crystals of Silicate-Oxyapatites CaLn4(SiO4)3O
,”
Inorg. Mater.
,
11
, p.
1137
.
30.
Stokes
,
J.
,
Presby
,
M.
,
Hoffman
,
L.
,
Setlock
,
J.
,
Salem
,
J.
, and
Harder
,
B.
,
2024
, “
Effects of Molten Silicate Reactivity on High Temperature Erosion Behavior of Plasma Sprayed Yb2Si2O7-Based EBCs
,”
Surf. Coat. Technol.
, 494(Part 1), p.
131078
.10.1016/j.surfcoat.2024.131078
31.
Harder
,
B.
,
Presby
,
M.
,
Salem
,
J.
,
Arnold
,
S.
, and
Mital
,
S.
,
2021
, “
Environmental Barrier Coating Oxidation and Adhesion Strength
,”
ASME J. Eng. Gas Turbines Power
,
143
(
3
), p.
031004
.10.1115/1.4049414
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